Added minified copies of jQuery 1.11 and jQuery migrate 1.2 to the stronger libs directory.

While using the jQuery CDN has its benefits (particularly around caching) it was
hurting my development productivity when I was offline - so we won't use the CDN
for now.
Added local copies of highcharts library to static/stronger/js/libs

Relying on a CDN was hurting my workflow when I was offline - so we will
use a local version during development stage.