regression on ofLaunchBrowser from documentation drive
fix incorrect signature for ofGetTimestampString
Merge pull request #2977 from admsyn/fix-timestamp-string-signature

fix incorrect signature for ofGetTimestampString
Merge branch 'master' of https://github.com/openframeworks/openFrameworks.git into rexgo
ofGstVideoPlayer fix inacurate video frame count
Merge pull request #2979 from yesyesnono/master

ofGstVideoPlayer fix inacurate video frame count
Merge branch 'master' of https://github.com/openframeworks/openFrameworks.git into rexgo