switch to jsRender and add datarepeater plugin

* removed dependency on jQuery templates that are now totally removed
from jQuery and added a dependency to jsRender instead for client side
javascript templating.
* Added a 'datarepeater' plugin to at page load repeat a template into a
container element from a url that returns items as a JSON object.  To
the container, just apply class 'datarepeater' and add attributes
'data-json-url' and 'data-template'.
* places that accept a list of items for templates now accounts for the
supplied json data already being an array. (was just assuming items
property or falling back to putting a single instance object into an
array.
* minor refactorings for renaming variables with proper case