Add a quantisation parameter to raspivid to allow greater control
including variable bitrate if combined with birate = 0

Updated docs to match.
Merge pull request #121 from JamesH65/quantisation

Add a quantisation parameter to raspivid.
Add a inline headers option. Inserts PPS and SPS headers
on each I-Frame
Merge pull request #122 from JamesH65/inline

Add a inline headers option
vcos: log messages to stderr rather than stdout
mmal: Avoid building mmal components and add rules for mmal_vc_diag