Set the audio 'original duration' during initial events parsing

This is the point at which the start/stop events for the audio are
correctly matched up with eachother; doing it later can give
incorrect results if an 'end recording' event was missing from
the events file.
Add the 'mkclean' step for audio-only recordings
MainCanvas height binded to its parent to avoid using percentHeight.
 - add log on FS client when user joins voice conference
 - add log when handling user joining voice conference
 - add more logging
 - remove meeting from FS list of meetings when meeting is destroyed
 - missed one are where we are not propagating message from Meeting Actor
Updated bbb-lti to fix issues with grails 2.3.6
Merge pull request #382 from speakserve/fix-window-maximize-lockup

MainCanvas height binded to its parent to avoid using percentHeight.
RaP: video processing robustness improvements

Makes it handle possibly corrupted video files with less chance of
breakage. Use features from newer ffmpeg release to simplify the video
trimming - in particular, using -ss as an input option is accurate now.
 - add logging on why joining into conf from echo test in CHrome fails
 - add logging to trace why disconnect callback isn't called when joining the conf using chrome
 - move callback to inform client that call has ended
Switch recording processing to use poppler instead of ghostscript
Change the way the lti endpoint is configured and used
Merge pull request #383 from jfederico/master

Changes to the LTI componet
 - make joining of voice and closing mic settings window a 2-step process to prevent race condition
 - init on creation complete not when added to stage as sometimes it may create multiple windows
 - tool to cleanup transifex downloaded files