Include a user-agent for API Requests

So new tokens are named correctly on TMBO, and for better traffic
modelling.
Simplify image centering code.

That shit looked like it came from Stack Overflow, and I couldn't find
where I got it for attribution, so out it goes!
Update fit on image load and presentation.

This fixes a problem that was reproduced by:
• View image
• Return to list
• Rotate device 90°
• View image

The image should have been fitted to the viewing window, but instead it
was sized for the previous rotation.
Cleanup
Merge pull request #1 from jimjkelly/develop

Add icons for all resolutions, [this is jerry] style
Remove the old model, stub out a new one.
Builds and runs, but the new model stubs aren't connected to the ListViewController yet.
ListViewController is connected to the stubs
New model store working
The incremental store stuff is gone, and the list view works correctly and gets new uploads.
Still a lot more to do, but no *something* works end to end.
reminders
Use git submodules instead of Cocoapods
I'm still not decided about Pods. On the one hand they're a big hammer for a relatively small problem, requiring changes to the project file(s) and the way you interact with it.
On the other hand, if a git repo goes away, your submodule is gone and you better hope someone has a checkout that they can use to reconstitute the loss.

I think the second option is most reliable, since the required sources can be hard-checked-in if a repo disappears since the project is probably dead if that happens anyway.
Initial README
Working -authenticateUsername:password:completion:
And some other debugging stuff
Authentication failure logic.
Authentication failures in the model are now handled by calling a registered target/action pair, which is currently stubbed to the App delegate.
Slightly better dev token stuff
That assert isn't being helpful, being *before* the dev token injector
Initial implementation: updateUploadsWithType:inRange:completion:
Slight change in the calling convention, but this method isn't used anywhere yet and it's a small change.
move TMBOMakeRange into impl file
Rename TMBOImageListViewController -> TMBOUploadListViewController
push detail view controller based on upload type
Bugfix

No direct access to ivars!