Added invokeApply parameter to $http to skip apply

[Utsav2]

There are a bunch of times when we don't want a $rootScope.$apply after an http request succeeds. This stackoverflow question gives a good use case: polling.
We can also use this to do scope specific digests, which really helps performance and snappiness on mobile devices.

It also gives us a little more control over the API, and also makes it similar to $timeout.

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[Utsav2]

I signed it!

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CLAs look good, thanks!

[lgalfaso]

so if skipApply is true, then resolveHttpPromise will not get called?

[Utsav2]

Yeah, that's a mistake.

[Utsav2]

Could you have a look at this #12557? I've fixed the problem.