Introducing the CSP Fixer

@devoncarew

Devon: sorry, a couple of unrelated trivial changes have crept in.

I should also add tests.

Also note that I deliberately exposed the feature only in the form of an explicit action. I didn't want to build it into the Bower install/update sequence or anything like that because it's too early and too risky.

I think it's actually useful in this case, and I'd like to use this as an opportunity to test drive a multi-item action, to be later reused in other places (e.g. we currently can't remove multiple projects at once from the workspace).