Kit: Handle device changes

Fix the updating of kits as devices are added/removed. This never
worked as intended due to the DeviceManager not sending the signals
I expected it to send, but masked by the Kits options page doing
the right thing for us.

Change-Id: I2d42ff7c1b8f6d795e20aebd114d723304904d4b
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
Do not accumulate connections for updating external file warning

The project explorer was accumulating connects to editors' changed
signals (for editors on "external" files).

Change-Id: Ia961a76ca9b67429a682973bc68acd483d4cd127
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Ukrainian translation update for 2.8

Change-Id: Ieefff3b428a7bf45270ae80681d1b8b029bacfce
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>