Added accept header to xhr request.
Merge pull request #17 from mdobson/accept-header-fix

Added accept header to xhr request to prevent text/csv issues.
Change usergrid.js link in Quickstart

Many people at trainings get confused with the location of the usergrid.js file. I figure that integrating a URL that works is probably an easier way to get them started.
add new return types to SDK
Merge branch 'master' of github.com:apigee/usergrid-javascript-sdk
updated minified version of sdk
fixed bug creating entity with no "name" field