Create angular directive for modules #302
Description
We're currently only using ng-include with a naming convention for retrieving the template. This does not introduce isolate scope and results in a relatively monolithic structure. Also, having directives will serve as a place to attach functionality that is currently in designer controller. For example "addStep/removeStep" are good such candidates.
This issue is a prerequisite before proceeding further with converting say step to a proper angular directive - #298