[packman] Clean up PMOBS part 1: gstreamer

[Detlef Reichelt]

Hi,

i've setup an own OBS to fix/cleanup gstreamer for PMOBS, as you can
see (1), for every $DIST an extra version of gstreamer. Also build
required packages only if $DIST doesn't fullfill the requires. For
example:

1140_libmms

Build libmms up to 1140, 1210 and later have libmms in oss.

If nobody have a problem with this style, i ci it to PMOBS.

Detlef

(1) http://drcux.de/gstreamer.pdf