v2.5.1

First native GitHub release (using Squirrel).
Option to provide feedback when uninstalling.
Uninstalls CodePlex ClickOnce app.
All references to CodePlex removed.
Improved management of API keys.
Bugfix: Continual retry to delete recurring all-day events
Bugfix: Failure to retrieve master for Google recurring event.
Bugfix: Saves failing to Google after adding calendar ID to event.
Bugfix: Cannot find shared Outlook folder.
Bugfix: Catch failure when checking for update on GitHub.
Bugfix: DND for reminders.

Merge branch 'master' of https://github.com/phw198/OutlookGoogleCalen…

…darSync

Moved source files to src directory.