Request: Allow extension names and command keys with 2 characters

[Blazeflack]

Currently there seem to be a restriction in place which prevents the use of extension names and/or command keys with less than 3 characters.

If possible I would at least like this restriction lowered to 2 characters (but I don't see why it needs to be higher than 1).

[vladfrangu]

@GilbertGobbels