Include TortoiseGitProc.exe full path in About Dialog

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Handle libgit exception of git_resolve_ref()

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
CBranchCombox need not to get current branch when loading branch list

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Prevent null exception when calling DnsFree()

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