Implements a manual and automatic update checker with support for both release and testing update channels, allowing users to stay as up to date as possible. It is fully compliant with privacy regulations around the world, as it stays completely silent and inactive until the user gives the Ok to connect to GitHub for the latest releases.
Moves the menu for StreamFX to the primary menu, so that it is not hidden under tools. This makes it clearer to the user if their installation of StreamFX is working correctly, in addition to reducing the steps necessary to use the menu.
Also the 'About StreamFX' dialog now actually shows up for every update, as expected.
Q_INIT_RESOURCE and Q_CLEANUP_RESOURCE can't be called from within a namespace and instead have to be in outside of the namespace, so by moving them into small inline functions we can fulfill this restriction.
Related: #192#155
Implements support for various new UI features that weren't possible up until now, such as an 'About StreamFX' window with a thank you to everyone that supported the project up until now.
