Get new phones and upgrade to Java 8

[jamestmartin]

Java 8 has a whole bunch of useful new features relevant to us, including

• default and static methods in interfaces
• lambda expressions (!!!-- this would be extremely useful since we have to use anonymous classes all the time) and functional interfaces
• streams (I use these all the time when they're available)

It's been out for ages, but our phones are too old to support it. Our phones are pretty old in general, and new ones would be nice. We should do a cost analysis and check whether ftc_app can work with Java 8.

This is not a particularly high-priority feature, it would just be nice.