Denser control positioning

Signed-off-by: Yue Lin Ho <b8732003@student.nsysu.edu.tw>
Signed-off-by: Sven Strickroth <email@cs-ware.de>
Make sure rebase is never executed on CLI on pull

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Drop "allowRebase" parameter

This was only used by ReferenceBrowser, but I see no reason why we should explicitly forbid or auto-deselect it there.

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Disable "rebase after" checkbox if remote is a URL

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Auto-toggle "Rebase after" in Pull and Fetch Dialog if not supported

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Document navigation to a separate section

Signed-off-by: Yue Lin Ho <b8732003@student.nsysu.edu.tw>
Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Signed-off-by: Sven Strickroth <email@cs-ware.de>
After removing a variable from CEnvironment the environment was broken

 * if the variable was not found, adding new variables is not possible any more
 * if the variable was found, the environment ended directly before the next one

Fix regression of 7ac6cc65047ed4565ab9731d705d28c01f738b51.

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