Fixed issue #2342: Ignore whitespace blame option does not work

Signed-off-by: Aleksey Vasenev <margtu-fivt@ya.ru>
Signed-off-by: Sven Strickroth <email@cs-ware.de>
RebaseDlg: Allow to split commits

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Do not disable Amend if error occurred

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Disable Amend if cherry pick is active is

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