Replace core_find with native find
Replace core_find with native find

Native find is much faster. As for future Windows work,
this is no problem, as the retained solution involves
using find.exe from GnuWin.

rabbitmq/erlang.mk,ingwinlu/erlang.mk,bsmr-erlang/erlang.mk,KrzysiekJ/erlang.mk,ninenines/erlang.mk,a12n/erlang.mk,hairyhum/erlang.mk,nevar/erlang.mk,jj1bdx/erlang.mk,crownedgrouse/erlang.mk