Commands accept as argument: user, host, room, service
and return as result JIDs
Commands that change in API v3:
get_room_affiliations
muc_register_nick
muc_unregister_nick
set_room_affiliation
status_list
status_list_host
subscribe_room
subscribe_room_many
unsubscribe_room
Correct Makefile clean targets
Fix a few more include() -> include_lib() for depedency includes
Use project_app_dirs to reference elixir app from rebar3 (lib_dirs is
no longer supported)
The changes are very similar to those from previous commit:
* Now there is no need to pass validating function in
gen_mod:get_opt() and gen_mod:get_module_opt() functions,
because the modules' configuration keeps already validated values.
* New functions gen_mod:get_opt/2 and gen_mod:get_module_opt/3 are
introduced.
* Functions gen_mod:get_opt/4 and get_module_opt/5 are deprecated.
If the functions are still called, the "function" argument is
simply ignored.
* Validating callback Mod:listen_opt_type/1 is introduced to validate
listening options at startup.
