chore(ngCsp): add e2e tests

Also changes `connect:devserver` and `connect:testserver` to conditionally serve files with csp headers when the path contains `.csp` somewhere.

Depends on https://github.com/angular/dgeni-packages/pull/70 to be merged and updated dgeni-packages to be included in angular.js
do all the browsers we support respect CSP headers? I'm just not sure about safari 6