Transition to AFNetworking from MWNetworkOp.

Added cocoapods Podfile and through it, AFNetworking and HPPLE.
Note: build script is in place but commented out. Also, auto
integration with workspace instead of xcodeproj is still too
messy so the build script uses "no-integrate" flag and we
manually reference the files we need for now.

Fix for auto-login crash after creating an account.

Handles ssl fail-over in more central place, not just in
article retrieval.

Search results ordering updated to reflect recent
update to mobile web search.

Fix for edit token parameters being deprecated.

Scale Wikipedia Zero message bar (at bottom of screen)
to scale with other native interface elements on iPads.

Change-Id: I991fac86a8788d3fd25595849b618a3d1ee7e699