Fix assets URL (expected to change... again)
Forge XZ downloads now use temp files local to MultiMC, files are removed.
Implement user info stub for newest minecraft snapshot
Fix console window (now not a QDialog)

It now opens and coloses as expected, depending on user
preferences and the status of the various processes involved.
Console window geometry and state are remembered between runs.
Stuff, stuff and stuff. Basic functionality works. Still needs testing.
Merge remote-tracking branch 'upstream/develop' into quickmod

Conflicts:
	gui/MainWindow.cpp