Remove "/role-select all"

[Zabuzard]

Recently, we merged #351 and it is pretty cool. However, it has two subcommands:

• /role-select all - users can pick any of the existing roles on the server
• /role-select choose - users can only pick roles that the mod pre-selected

I do not see a valid use case for /role-select all. Why would you want people to give the possibility to choose from ALL roles (including staff assistant, moderator, ... and other dangerous roles).

In fact, it only takes a careless mod to accidentally run /role-select all, hit enter and oops people could already give themselves Moderator, Staff Assistant and other "protected" roles (and you wouldnt even notice).

I propose to remove /role-select all and lift /role-select choose to just /role-select.

[Zabuzard]

(@Tais993 for visibility)

[Tais993]

I agree, kept it since it was in the original implementation.