[Suggestion] Allow to set directories for downloads and for installation.

[vetall812]

I'd like to point where to install the game and where to store additional data (downloads / backups).

[RabblerouserGT]

I'm curious if this would allow for multiple builds to be installed and able to be hot-swapped at will. I was able to do so on remyroy's launcher through one of the dropdowns. I believe that a good idea worth using.

[ParaplegicRacehorse]

I'd like this, too. Particularly since selecting install location would allow me to point it at my existing, non-Catapult, install.