Update Profiles settings icon

Switch to vector drawables to fix blurry drawables

Change-Id: Id3f5e3ad408c4d17659d941f68853379b07c688f
Rename Profiles to System profiles

L includes 'Users & Profiles', rename ours to distinguish features
and prevent confusion.

Change-Id: I5a148dcf5fea1b24448d254105b0bd6904a4ddd8