Replace/Replace All button should not be default button, correct the tab order and accelerator

Press Enter key should not do replace

Based on TortoiseSVN revision 25559

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
TortoiseGitMerge: Fix crash when pressing Home key if Wrap Long Lines is enabled

Based on TortoiseSVN revision 25561

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