Fixed all messageboxes that can use struct object as self name
(e.g. m for messageboxes in mainwindow). Should help to avoid some
errors.
Added possibility to copy server's credentials into clipboard
for ease of sharing.
Refactored the way URTrator working with profiles - now everything
that could be taken from internal cache will be taken from cache.
The very same as with servers.
Moved all callbacks from callbacks to events, so we achieve full
asynchronity here and can launch anything in goroutines :).
Moved MainWindow-related game launching functions into another
file (mainwindow_launch.go).
Made quick connect widget working. Note, that even if you're on
Favorites and trying to connect to one of favorited servers but
with quick connect - you still have to choose right profile
near Launch button!
Maybe something else I forget.
