This patch implements the MMS protocol, by using libmms. It is quite
experimental: it does not support seeking yet, and it is currently
using synchronous I/O, which causes MPD to hang while waiting for the
server.
mpd uses some additional files to work, such as pid_file, state_file,
db_file, etc. when running mpd as non-root user, it is often that those
files end in ~/.mpd
in that case, we end up with 2 entries in a user's home, .mpdconf and
.mpd - which clutters homedirs.
this patch allows ~/.mpd/mpd.conf as an alternative to ~/.mpdconf,
allowing for a cleaner homedir
MPD's HTTP client code has always been broken, no matter how effort
was put into fixing it. Replace it with libcurl, which is known to be
quite stable. This adds a fat library dependency, but only for people
who need streaming.