no longer use mocha
remove mobile demo
remove unused image
fix travis not using master account on master
use more specific fonts in demo
Check leaf nodes are still in dom on line rebuild

Fixes #88
Choose delta with fewest insertions, fixes #98

When trying to pick a delta describing document change. Previously used
delta with fewest operations.
set up npm prepublish
cleanup on npm postpublish
install grunt before travis calls npm install

apparently npm prepublish is called on npm install
bump version