Use manual conversion instead of DesktopAppConverter for Windows Store version, optimize files included in Appx, automate build

[PawelTroka]

Instead of using DesktopAppConverter we are now safe to use manual conversion since we know exactly what our installed does from analysis of VFS folder in DesktopAppConverter converted app.
See: https://docs.microsoft.com/en-us/windows/uwp/porting/desktop-to-uwp-manual-conversion

It's easy and can provide us easier and faster deployment and testing. Output Appx will be also made smaller and more optimized since all unneeded trash produced by the installer will not be included.

It's also easy to automate it since it is only copying files to some directories and calls to some executables like MakeAppx.

[PawelTroka]

Resolved with commit a30e403.
In comparison appx file is now 16.5MB instead of 37MB.