Merge pull request #197 from binlain/master

Fix crash in node and properly pipe streams.
Fix timemark to seconds when no hours/minutes are present
Merge pull request #200 from njoyard/fix-timemark

Fix timemark to seconds when no hours/minutes are present
Add getAvailableCodecs and check codecs in _prepare
Add check for codec encoding capability
Add getAvailableFormat, add format check
Only check format/codecs when specified
Fix capability detection not handling avconv/ffmpeg output differences
Fix bitrate arguments tests
Use local mocha for tests
Merge pull request #203 from njoyard/add-capabilities

Add codec and format capability helpers
Merge pull request #205 from njoyard/fix-tests

Fix bitrate arguments tests
Inherit from EventEmitter, deprecate onStart/onProgress/onCodecData
Deprecate callbacks in favor of 'end' and 'error' events
Update tests to evented API
Fix wrong mergeToFile callback chaining
Enable kill an renice runnning ffmpeg process
Add tests for .kill and .renice
Merge pull request #202 from njoyard/add-processcontrols

Enable kill and renice running ffmpeg process
1.6.0