extras/bacon_cape: removed USB device IP and made paths relative

Removed references to 192.168.7.2 and replaced with window.location.hostname and relative paths
demo/blink.py: created a simple Adafruit_BBIO Python demo
demo_flot.html: enable specification of different address

http://beagleboard.github.io/bone101/extras/bacon_cape/demo_flot.html?address=beaglebone.local
should work after this as long as a BeagleBone is on your LAN