[opensuse-buildservice] osc: patch to enhance "osc vc" command to support MeeGo style changelog

Hi, Please help me to review this patch to make "osc vc" to support the MeeGo style changelog, thanks! Background: the origin "vc" osc sub-command will call "/usr/lib/build/vc" script which is shipped with "build" package. And there's a corresponding 'vc' shell script for MeeGo in meego-packaging-tools with the similar feature and purpose: to generate changelog header in *.changes automatically. This patch will make 'osc vc' to detect MeeGo packages firstly, and call proper 'vc' script accordingly. - jf.ding