Previous versions of this plasmoid used to manually fill a ListModel
with the list of available fonts on the system, which would end up
blocking the main thread while that's happening. Instead, use the QML
FontDialog which makes the experience a bit better.
This commit overhauls the repository structure such that it separates
the project into multiple repositories, one for each subproject. This
repository will be moved to the AeroShell group, and most importantly,
the installation method changes from locally installed modifications, to
CMake-based installation, in preparation for AUR packages, and possibly
packages for other distros.
Migration details are in INSTALL.md, which are highly recommended, if
not required to uninstall any old instance of AeroThemePlasma.
