feat(features/interaction-events): add touch events

Added touch events via the hammer.js library, run npm install
to get it.

Related to bpmn-io/bpmn-js#84
chore(touch): move touch interaction into separate module

Related to bpmn-io/bpmn-js#84
feat(draw/Renderer): render connections + shape outline
chore(features/interaction-events): rename events -> eventBus