fix(travis): enable travis-ci builds
chore(dependencies): update grunt-contrib-jshint to v0.7.0
chore(dependencies): update semver to v2.2.1
refactor(utils): replace DOM.trigger() with $.triggerHandler
refactor(errors): fix minErr warnings in build
fix($drag): improve caching of mouse position
docs(demo): implement simple demo page
docs(README): add link to demo page
chore(Gruntfile): add gh-pages task to gruntfile