Fixed multiple update threads from running deeper in the code than
disabling the login button.
Fixed creation of empty directories for currently uninstalled packs.

Signed-off-by: Dalton Pelc <daltonjpelc@gmail.com>
Finished fixing multiple login attempts corrupting the launch.

Signed-off-by: Dalton Pelc <daltonjpelc@gmail.com>
Restructured internal framework to better support adding custom modpacks

Signed-off-by: Dalton Pelc <daltonjpelc@gmail.com>