Adding support for new donation sources to credits screen, and additional details on exceptions when crashes are reported

Fixing alpha_mode on Blender animated titles, which was causing the backgrounds to be opaque. Now the backgrounds are transparent as they were intended. Also fixed a small bug with "recently opened" logic, which was broken.

Fixing a bug when switching between Thumbnail and Detail views on the Project Files view. Also, some misc syntax errors related to switching Keyframe interpolation modes.

Fixing a few Python exceptions related to invalid clip ids, invalid clip queries, and clips with missing 'reader' attributes

Adding exception/stacktrace metric code, to send unhandled exceptions to openshot.org for futher analysis (if user enabled metrics)

Adding margins to QDockWidgets in the UI file, since Windows now has no margins around those widgets

Adding support for new exception handling, and logging/metrics the primary crashing function reported in the stack trace.

Updating profiles with 2.5k and 4k profiles from the latest MLT, which are compatible with libopenshot. Thanks MLT!

Adding vector title templates for film ratings (G, PG-13, R) etc... Also extending the # of text elements supported on the title editor, so all film ratings can be edited completely.

Adding 28 presets for Bezier curve handles (ease-in/out, bounce, etc...)... as opposed to the old bezier mode (which used 40% handle values for 1 generic smooth curve). Now, the curve can be quickly adjusted by using these presets, changing any animation in OpenShot. Also updating translations. Also, adding in some compatibility for old project files, which now contain in-compatible keyframe curve handle values. Basically, opening an older project (up to version 2.1.0-dev) will auto translate the keyframe handles into the new percentage format (same syntax used by CSS). Also fixing a bug related to double clicking property editors (i.e. color picker)

Integrating more GitHub API functionality into OpenShot build server, to help automate the creation of torrents, new releases, and uploading files to the correct GitHub releases.

Refactor tutorial logic, to grab the QWidget at runtime, rather than app start-up, which fixes a crash. Also fixing a crash when using context menu on transitions window.

Added support for dropping files directly on the timeline from the OS! This also fixes a big crash caused by unexpected things being dropped on the timeline. Also, fixed some drag and drop JS issues related to Z-index and dropping items on the timeline.

Saving settings now on close of the Preferences dialog (instead of application close). No longer adding "backup.osp" to the recent project list. Fixing an issue when clicking pause, and then setting a keyframe at that exact spot (which would select the wrong frame).

Fixing performance related issues with new caching framework, and moving the rendering code outside of Angular scope... so we don't have to use a scope.apply(), which is very CPU expensive.

Fixing a silly error when opening legacy OpenShot 1.4.3 project files, related to utf-8 encoding. Basically, if any file paths contain non ascii characters, it would fail. This fixes #249.

Disabling ssl validation, since ssl is not being used, and some users have reported errors with cx_Freeze version of OpenShot crashing on missing ssl files.

Fixed lots of bugs relating to selecting the correct position to insert a keyframe. Dragging clips, resizing clips, dropping clips, selecting cips, etc... all needed hooks to update the correct frame for the properties window. Also, fixing some undo/redo regressions, and adding a refresh signal when undo/redo is used, to update the current frame of video (i.e. since things just changed).

Improved property editor to ignore undo/redo history while dragging, so it doesn't build up a huge history. It only records the final value in the undo/redo history.

Fixed a few bugs related to opening an .ops project or media file via command line args (i.e. openshot "my_project.osp"). Also, increased the max zoom in on the zoom slider, to 1 second=100 pixels (which is probably too close for most)... but useful when you are trying to sequence lots of fast flashing images. Also fixed a regression with the new caching code, when the app is starting up (race condition).