Per message from Joe, changed name of feature from "Runtime
Permissions" to just "Permissions". Still sometimes referred to it as
"runtime permissions" in descriptive text, as appropriate.
I considered renaming the feature page to ./permissions.jd , but
given the short time, I decided against it--there were too many
ways a file rename could break things, and this is just a temporary
"preview" page anyway.
See first comment for stage location.
Change-Id: I0ce36d99ea2377cf9fa7ac72b2f182dedb5c38e8
