[binary addons] Add automatic dependency handling and move RSXS and some Visualizations to addons

This adds automatic dependency handling for cmake based addons by using the depends folder in existing binary addons.
Addons are first downloaded and extracted, then we check if the depends folder exists and handle addon deps dynamically. Tested on linux

Additionally a few screensavers and visualizations are moved over to addons.
@Montellese @jmarshallnz @notspiff ping for platform stuff and sanity checks

Note about projectm: After sinking hours on end into trying to fix the mess that projectms buildsys is and trying to get it compiled static _without_ unresolved symbols, I gave up at let it build dynamically. On linux libprojectm.so is copied to the addon install path.