Implement additional fingerprint flows in Settings.

- new onboarding flow ("locate sensor")
- changed sensor location image
- changed in-app sensor icon
- remove fingerprint animation since it caused people to
want to tap on it.
- remove enrolled fingerprint templates when switching back to "none" or "slide"
- use real in-app icon for fingerprint
- much improved layout
- basic landscape layout working
- added 250ms delay to final enrollment step so it's not so jarring
- delete is now working
- rename wired, but not functional yet

Bug 19592835

Change-Id: Ie3e73a2fc8f834f1b90e2746c4cc841216aa6031