Revert "Switch to new Superuser"

This reverts commit 98d71ec9afe93251f8a19360e80fe9431c5518c1.
Launch SuperSU from Settings

If SuperSU is installed, show an entry in Settings below
"Developer options", which launches SuperSU when tapped.
At boot time SuperSU will detect if com.android.settings
contains the resources from this patch, and if so it
will hide itself from the launcher. This was implemented
in v1.85, so we only show the entry if the installed
SuperSU version is at least that.

PS3 - Added material green icons for SU

Change-Id: I2af95a1a4396101ff87448cd0ae20addf235af52