Mention Merge "No Commit" option in documentation

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Reduce local variables in CAppUtils::Merge method

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Fixed issue #1500: Support git merge --log option

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