No back icon in action bar of APN Settings

When entering the APN menu, the actionbar is missing a back
icon allowing the user to go back to the previous pane.

Added parentActivityName in ApnSettings, to enable action
bar back icon.

Change-Id: Iee8bb420f47c0e2c0d9a43739f534466abba30db
Translation: import russian translation from crowdin.net

Change-Id: I0f767f18de078bd3c1b9c42fd7b19f248df28769
Signed-off-by: Dirk Rettschlag <dirk.rettschlag@gmail.com>