refactor for forj-docker cli init command

* updating docs for forj-docker getting started.
* give bare connect task ability to start a dev container
* refactor for cli
* add feature so we can load any task provisioner found
* use rake rundev and rake runbuild to toggle between
  using dev or no dev environment
* small update to README for setting up dev env.
* add support for forj-docker gem to init and rake build

Change-Id: I6dcaf4ccda00a9116a424df6f037e35056154f87