Add control via keyboard (#6)

* Correct angle documentation

* Correct body component doc

* Add a config module with px 2 meters

* Create component to map input

* Add components for mappable actions

* Add component for elastic manipulation

* Add node to modify physics

* Add controllable node

* Add dasher node

* Add control mapper system

* Add component to limit velocity

* Add node for limiting velocity

* Add systems to move and dash

* Use meters in physics systems

* Correct documentation in render system

* Add elastic manipulation system

* Update factories to use new components

* Update main app to use new systems

* Ignore dist dir

* Also ignore cache

* Ignore personal configuration files

* Add system to reduce velocity

* Add changelog