Minor edits to CSP 1.1

I've made a number of minor edits to the CSP 1.1 specification.  I
believe these are uncontroversial, but I'm happy to discuss/revert any
of them:

* The status of this document now reflects that CSP 1.1 is an
evolution of CSP 1.0:
https://dvcs.w3.org/hg/content-security-policy/rev/d8b339f778ef

* Violation reports now contain column numbers:
https://dvcs.w3.org/hg/content-security-policy/rev/e49a598515f1
https://dvcs.w3.org/hg/content-security-policy/rev/fb76281884d7

* I've removed a sentence fragment:
https://dvcs.w3.org/hg/content-security-policy/rev/952981d6283a

(I've also made some non-minor edits, which I'll describe in subsequent emails.)

Adam