This commit adds completion support for the plugin commands. It will try
to complete partial namespaces to the full namespace string. If the
completion input is already a full namespace string then it will add all
the matching plugins in that namespace as completions.

This lets the user complete to the namespace first and then tab-complete
to the next level if desired.

```
(lldb) plugin list a<tab>
Available completions:
        abi
        architecture
(lldb) plugin list ab<tab>
(lldb) plugin list abi<tab>
(lldb) plugin list abi.<tab>
Available completions:
        abi.SysV-arm64
        abi.ABIMacOSX_arm64
        abi.SysV-arm
        ...
```

This commit adds three new commands for managing plugins. The `list`
command will show which plugins are currently registered and their
enabled state. The `enable` and `disable` commands can be used to enable
or disable plugins.

A disabled plugin will not show up to the PluginManager when it iterates
over available plugins of a particular type.

The purpose of these commands is to provide more visibility into
registered plugins and allow users to disable plugins for experimental
perf reasons.

There are a few limitations to the current implementation

1. Only SystemRuntime and InstrumentationRuntime plugins are currently
supported. We can easily extend the existing implementation to support
more types. The scope was limited to these plugins to keep the PR size
manageable.

2. Only "statically" know plugin types are supported (i.e. those managed
by the PluginManager and not from `plugin load`). It is possibly we
could support dynamic plugins as well, but I have not looked into it
yet.

Partly, there's just a lot of unnecessary boiler plate. It's also
possible to define combinations of arguments that make no sense (e.g.
eArgRepeatPlus followed by eArgRepeatPlain...) but these are never
checked since we just push_back directly into the argument definitions.

This commit is step 1 of this cleanup - do the obvious stuff. In it, all
the simple homogenous argument lists and the breakpoint/watchpoint
ID/Range types, are set with common functions. This is an NFC change, it
just centralizes boiler plate. There's no checking yet because you can't
get a single argument wrong.

The end goal is that all argument definition goes through functions and
m_arguments is hidden so that you can't define inconsistent argument
sets.

This is a follow-on to:

https://github.com/llvm/llvm-project/pull/82085

The completer for register names was missing from the argument table. I
somehow missed that the only register completer test was x86_64, so that
test broke.

I added the completer in to the right slot in the argument table, and
added a small completions test that just uses the alias register names.
If we end up having a platform that doesn't define register names, we'll
have to skip this test there, but it should add a sniff test for
register completion that will run most everywhere.

This reverts commit 21631494b068d9364b8dc8f18e59adee9131a0a5.

Reverted because of greendragon failure:

******************** TEST 'lldb-api :: functionalities/completion/TestCompletion.py' FAILED ********************
Script:

Most commands were adding argument completion handling by themselves,
resulting in a lot of unnecessary boilerplate. In many cases, this could
be done generically given the argument definition and the entries in the
g_argument_table.

I'm going to address this in a couple passes. In this first pass, I
added handling of commands that have only one argument list, with one
argument type, either single or repeated, and changed all the commands
that are of this sort (and don't have other bits of business in their
completers.)

I also added some missing connections between arg types and completions
to the table, and added a RemoteFilename and RemotePath to use in places
where we were using the Remote completers. Those arguments used to say
they were "files" but they were in fact remote files.

I also added a module arg type to use where we were using the module
completer. In that case, we should call the argument module.

[lldb] Part 2 of 2 - Refactor `CommandObject::DoExecute(...)` to return
`void` instead of ~~`bool`~~

Justifications:
- The code doesn't ultimately apply the `true`/`false` return values.
- The methods already pass around a `CommandReturnObject`, typically
with a `result` parameter.
- Each command return object already contains:
	- A more precise status
	- The error code(s) that apply to that status

Part 1 refactors the `CommandObject::Execute(...)` method.
- See
[https://github.com/llvm/llvm-project/pull/69989](https://github.com/llvm/llvm-project/pull/69989)

rdar://117378957

This patch should allow the user to set specific auto-completion type
for their custom commands.

To do so, we had to hoist the `CompletionType` enum so the user can
access it and add a new completion type flag to the CommandScriptAdd
Command Object.

So now, the user can specify which completion type will be used with
their custom command, when they register it.

This also makes the `crashlog` custom commands use disk-file completion
type, to browse through the user file system and load the report.

Differential Revision: https://reviews.llvm.org/D152011

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>

This is part 2, covering the commands source.

Some uses remain where it's tricky to see what the
logic is or they are not used with AppendError.

Reviewed By: teemperor

Differential Revision: https://reviews.llvm.org/D104448

Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp -------------------------------------------------===//
```
However in LLDB most of our source files have arbitrary changes to this format and
these changes are spreading through LLDB as folks usually just use the existing
source files as templates for their new files (most notably the unnecessary
editor language indicator `-*- C++ -*-` is spreading and in every review
someone is pointing out that this is wrong, resulting in people pointing out that this
is done in the same way in other files).

This patch removes most of these inconsistencies including the editor language indicators,
all the different missing/additional '-' characters, files that center the file name, missing
trailing `===//` (mostly caused by clang-format breaking the line).

Reviewers: aprantl, espindola, jfb, shafik, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: dexonsmith, wuzish, emaste, sdardis, nemanjai, kbarton, MaskRay, atanasyan, arphaman, jfb, abidh, jsji, JDevlieghere, usaxena95, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D73258