Raise minimum API level to 16 (Android 4.1 Jelly Bean)

[justinanderson]

As of 11/1/2014 80% of our users are on 4.1 or higher.

[hasitpbhatt]

What exactly is needed to be done in this task? Changing minSdkVersion to 16 and removing deprecated code before API 16?

[justinanderson]

@hasitpbhatt I should probably assign this to @sseligma. It's more of a parent task for other work going on with the sdk-16 and intrepid branches. This can probably be closed once those branches are merged into master.

We're overhauling the app to use Lollipop's UI style and to drop a lot of custom code we wrote to make Gingerbread look like KitKat, plus removing some 3rd party libraries that we don't want to use anymore, like ArcGIS for mapping and a pull-to-refresh library.