Incorporate Paul Stoffregen's Teensy 3.1 changes
Added theaterChase and theaterChaseRainbow

Added two new effect functions. theaterChase does a
theater-marquee-style chase, and theaterChaseRainbow combines the
theaterChase with the rainbow effect
Comments in examples now include wiring best practices
Tweaked 'best practices' comments in examples
Merge upstream changes