Add support for renaming modules

[plux]

Description

Add support for renaming modules.
Put cursor at modname in -module(modname), and trigger the rename command.
This will rename the .erl file (in the same directory), updated the -module attribute
and update references to the module such as:

• Function applications
• Type applications
• Implicit functions
• Imports
• -behaviour attributes

This PR also improves the "find references" functionality for modules, previously it only displayed function references.

There's a small race condition with Emacs erlang-mode as it wants to be helpful and suggest that the old filename doesn't match the new module name, you need to answer no when it asks if it should fix the module name.
Personally I have now disabled that check:
(setq erlang-check-module-name nil)
This feature could be handled by erlang_ls with a code action instead as
we already have a diagnostic to check the module name.
Could be a good beginner task 👍

[robertoaloi]

Personally I have now disabled that check:
(setq erlang-check-module-name nil)

Good point, we can include that in the provided Emacs config sample:

https://github.com/erlang-ls/erlang_ls/blob/main/misc/dotemacs

[robertoaloi]

This feature could be handled by erlang_ls with a code action instead as
we already have a diagnostic to check the module name.
Could be a good beginner task 👍

Yes! I hinted at that in the release notes, so let's craft an issue with that, pointing to the tutorial and let's leave it for new contributors.

[robertoaloi]

Nice one, thanks!