Role menu subcommands

[Kardbord]

Renames /create-role-menu to /role-select-menu and offers the subcommands create and update which allow an admin to update the menus after creation.

I also did some more thorough testing of the role select menus and found that interacting with large menus is painfully slow. To that end, I've added some configurable code profiling options to assist in identifying the slow parts of the code. They are agnostic to this particular issue, so I'm going to leave them in for next time! pprof is pretty slick. :)

With any luck, I'll be able to get the menu interactions running a bit quicker as part of this PR. As time allows, I may also try to instrument some even more robust profiling capabilities by adding user defined trace regions to interaction handlers.

[Kardbord]

• [x] Speed up interactions with large role select menus
• [x] Add user defined trace regions to interaction handlers (regions should only be defined if pprof is configured)