Fix imports to work as framework

[juanuribeo13]

This updates the AFNetworking dependencies imports to be system imports instead of local to fix the problem with cocoapods use_framework!

[damienrambout]

Please @mattt, merge this and push a new version on Cocoapods, otherwise it is impossible to use this lib as a pod framework.

[jairobjunior]

Hey @mattt, I am pretty sure that you have this in your backlog. I would love to stop using :git => 'https://github.com/juanuribeo13/AFOAuth2Manager.git', :commit => '7bf11369e5623a88313243001fb9b633e3ae15e6' for my prod version.

Thanks.

[juangdelvalle]

@mattt can you please release a new version on Cocoapods with this change, I have the pod referencing to @juanuribeo13 's change on my prod version and I would like to change it back.

[ealarco1]

@mattt I'd like to use this version as well. Could you please merge this and publish a new version?

[jrmiddle]

Piling on. Dear @mattt, as far as I can tell this is the last loose end for me as well.

[domness]

Would love this to get merged in :)

[DenTelezhkin]

@kcharwood @cnoon Guys, can you help with merging this in? Seems like very trivial thing to do.

Making my own fork for now...

[priteshshah1983]

+1

[tumatauenga]

+1

[kcharwood]

I'll get some more eyes on this project soon.