doc: Remove parenthesis around Since:
doc: Remove parenthesis around Since:

This confuse the parser, hence it does not endup in the doc and the
index properly.

centricular/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,centricular/gstreamer,shelsonjava/gstreamer,krichter722/gstreamer,krichter722/gstreamer,centricular/gstreamer,shelsonjava/gstreamer,krichter722/gstreamer,shelsonjava/gstreamer,shelsonjava/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,StreamUtils/gstreamer,krichter722/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,shelsonjava/gstreamer,centricular/gstreamer,jpxiong/gstreamer,centricular/gstreamer