RebaseDlg: Fix incorrect warning on unclean working tree on Squash(Conflict)->Squash sequence

Signed-off-by: Sven Strickroth <email@cs-ware.de>
RebaseDlg: Make Pick(Conflict)->Squash not to introduce unwanted commit

(fixes issue #2126)

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Optimize titles for putty tools in start menu

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

Signed-off-by: Yue Lin Ho <b8732003@student.nsysu.edu.tw>
[WIP] Fixed issue 1608: Add "Retry" button where applicable

Tested:
 * Switch
 * Merge

Un-test:
 * Pull
 * Push?
 * other command?

Signed-off-by: Yue Lin Ho <b8732003@student.nsysu.edu.tw>