Added test target and Travis CI.

This adds a basic test setup, moving the NAMapKit into the project as a development pod. There's a successful build [here](https://travis-ci.org/dblock/NAMapKit/builds/20212799). It spews a bunch of warnings, those should eventually be fixed ;)

[![Build Status](https://travis-ci.org/dblock/NAMapKit.png?branch=tests-and-ci)](https://travis-ci.org/dblock/NAMapKit)