Merge pull request #158 from saschagehlich/bugfix/timemark_undefined

Extensions#ffmpegTimemarkToSeconds returns 0 if timemark is undefined
dynamic progress line parsing, added 5m video to test onProgress, fixed presets since ffmpeg does not include libfaac support anymore
reverted test/extensions.test.js to master
Merge branch 'feature/dynamic-progress-parsing' into filsh