MobileFrontend/Photo upload/Upload Wizard mobile port

Some considerations when porting Upload Wizard to a mobile UI.

General

 * UW is built to create uploads that are of sufficient quality to meet the standards on Wikimedia Commons. This means: 1) Correct and legally valid licensing, 2) Useful titles, 3) Descriptions are a must. Categories are optional but strongly encouraged for advanced users. The only reason they're not required is that the Commons category system, by definition, requires proficiency in English.
 * Translating the entire flow to mobile makes it a pretty cumbersome process with lots of typing involved, even if we reformat it nicely.
 * In theory, we have the infrastructure needed to just dump files and add metadata later (stash). However, we wouldn't want to put that obligation on the community, but on the uploader. So one possible flow would be "dump your files via mobile, then log in and complete your uploads on your desktop".
 * If user testing a mobile-formatted UW prototype shows it to be unworkable, we may want to go down this path.
 * The UW front-end generating code is all over the place. A fork would be hard to maintain, but adding mobile codepaths to all DOM manipulation may not be much more fun.

Error cases
Uploads can encounter a number of tricky error cases which require user interaction or automatic resolution. Interactions that are reasonably straightforward on a large screen may pose major issues on a mobile device with limited screen real estate and inefficient text input. These issues stand out:


 * 1) Form validation issues. When you upload more than one file, and there are any errors in your submission (missing titles, descriptions, title blacklist matches, etc.), Upload Wizard will highlight all the errors and refuse to proceed. Even on the desktop users can get stuck here trying to find out where the problem is. Having a graceful error resolution UI would be a must for mobile.
 * 2) Title blacklist issues. All uploaded files are matched by name against commons:MediaWiki:Titleblacklist, and the API will refuse an upload if there is a match. (The file can be stored in the stash, but it can't be uploaded.) So, Upload Wizard currently asks the user to correct any titles which match the blacklist, e.g. filenames that are assigned by your camera like.
 * 3) User input issues. Users will often try to use the same title multiple times, or accidentally upload the same file. This then requires showing a warning, which gets us back to the problems under (1), or silently rejecting content.

Device specific issues

 * 1) "Safari on iOS does not support file uploading, that is, elements. If your webpage includes an input-file control, Safari on iOS disables it."  That means no iOS uploads except by app workaround.

Current bugs that affect mobile

 * 1) The coordinate (location) extraction is pretty fragile and will extract values like "-1" for altitude which it then refuses to accept. Lots of mobile photos will embed location info, so this is likely to come up. This should be ripped out and re-done, ideally with a map UI to select coordinates.