Allow to predefine a message for stashsave from CLI

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Improve error reporting

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Prevent possible concurrent access to gitdll

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Remove superfluous locks

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Hide the copy context menu item if not selected

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Log message context menu Select all also does copy

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>