Change-Id: Icd624ce174d9265fe551b9af4089b3660abc4142
Reviewed-by: Tobias Hunger <tobias.hunger@nokia.com>

Change-Id: I88cfb7839b41467e3f6b25bea329eb15765e440e
Reviewed-by: Tobias Hunger <tobias.hunger@nokia.com>

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Task-number: QTCREATORBUG-2410

Details: Use a global model for nicknames that is shared by all dialogs to solve the updating  problems. Make p4 plugin submit work again. Force a submit prompt in case of shutdown or editor close (as opposed to user clickling on "Submit").

With many git commands it is safer to disambiguate files from refs by
putting '--' in front of the list of files.

Also corrected a margin in the git submit panel.