Improve update migration of CheckNewer

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

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

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

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Call Run on current CGit object

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Fix possible memory leaks

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Fixed issue #2183: Explorer Property Page "Last modified" stays empty

Fix regression of e73a7eaac6b63bfdb1c7a63e1a28200c973937c1

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