Get rid of ejabberd.hrl header

The header consisted of too many unrelated stuff and macros misuse.
Some stuff is moved into scram.hrl and type_compat.hrl.
All macros have been replaced with the corresponding function calls.

TODO: probably type_compat.hrl is not even needed anymore since
we support only Erlang >= OTP 17.5

include/logger.hrl

@@ -42,3 +42,6 @@
             false -> ok;
             _ -> 'Elixir.Logger':bare_log(error, io_lib:format(Format, Args), [?MODULE])
         end).
+
+%% Uncomment if you want to debug p1_fsm/gen_fsm
+%%-define(DBGFSM, true).