docs(ngModelOptions): minor grammer error

Closes #9928
docs(guide/Modules): missing "a" in "a collection"

Closes #10001
docs(minerr/unpr): fix code example

Closes #10000
fix($httpBackend): compare timeoutId with undefined in completeRequest

httpBackend with ngMock browser.defer can never cancel the first deferredFn because the timeoutId returned by defer for the first fn is a zero value.
Compare timeoutId with undefined fix this issue.