playerData.c:
proper error checking

directory.c:
properly check myFgets() for errors
(it returns NULL on error)

inputPlugins/mp3_plugin.c
get rid of commas at the end of enums

interface.c:
we weren't using long long, so strtoll isn't needed
get rid of void-pointer arithmetic

sllist.c:
get rid of void-pointer arithmetic

compress.c:
get rid of C++ comments, some compilers don't accept them

Note that I personally like void pointer arithmetic, but some
ancient compilers don't support them :(

git-svn-id: https://svn.musicpd.org/mpd/trunk@4510 09075e82-0dd4-0310-85a5-a0d7c8717e4f