If an object has key that contains . or [], it is now correctly found
instead of searching for an inner object or array that does not exist.
Example:
var data = [{"key.withdot":"1"}]; // did not work before, works now
var data2 = [{"key":{"innerkey":"1"}}]; // still works
Updated test with new bugfix.
Code to access objects by path was taken from the solution of
http://stackoverflow.com/questions/6491463
When JSON objects are used to load chart data, nested / inner objects and
arrays can now be loaded, too.
See additional tests in spec/data-spec.js for examples, how to access nested
JSON object values