* ./plugins/mga/mga.c: removed the mgammx module and put the code in
    the chroma_i420_ymga module instead. This introduces a slight
    performance issue as we now need to memcpy() the Y plane, but I have
    some vout4 enhancements on their way which make this point moot.
  * ./debian/changelog: imported official Debian changelog.
  * ./debian/control: activated the vlc-mad and vlc-arts packages; package
    builds should now work again.
  * ./plugins/dvd/dvd.c: solved a symbol resolution issue when vlc was
    compiled without libdvdcss which overflowed the return stack.
  * ./plugins/ggi/ggi.c: ported the GGI plugin to vout4.
  * ./plugins/glide/glide.c: ported the Glide plugin to vout4 (untested).
  * ./src/input/input.c: prepared everything for multi-input mode; since
    no interface is yet prepared to handle this, I changed them so that
    they just use the first available input for now. This may break other
    things, but I promise I'll eventually repair everything :-)