Merge pull request #27 from pez4brian/master

Clean up remaining relics from QML conversion
Do not load frei0r plugins from system paths on Linux.
Fix saving recent files list after removing one.
Prevent possible crashes on failure to open file with playlist open.
Do not intentionally crash on MLT fatal and panic errors.
Add autosave feature.
Fix filter analysis when the clip is on the timeline.
Fix applying filter analysis results when the filter UI goes away.

This change creates a delegate QObject with a reference to the MLT
filter that receives the analyzeFinished signal. Now, you do not have to
wait for the analysis job to end before continuing to do other work.
Add warning at exit if there are incomplete jobs.
Fix marking doc as dirt at end of analysis.

And fix filter modifications marking doc as dirty for a playlist
project.
Fill timeline toolbar toggle buttons with highlight color.
Update all languages for string changes.
Fix typo (butoff) in glow filter UI update.
Add a Clean Files option to Windows installer.

Also, make the installer safer in case user removed the Shotcut folder
from the installation directory. And make uninstall safer in case user
moved uninstall.exe from the Shotcut folder.
Prevent dragging shots on timeline left of origin.
Fix moving a shot to an empty track.
Update all translations for release.
Ignore encoding preset properties beginning with underscore.
Fix setting encoding quality percentage for libx264.
Fix vid.stab for Windows crash loading results.

Need to reduce compiler optimizations from -O3 to -O2.