fix($resource): params should expand array values properly

Today, calling e.g.  var R = $resource('/Path/:a'); R.get({a: 'foo', bar: ['baz1', 'baz2']}); results in a query
string like "/Path/doh?bar=baz1,baz2" which is undesirable. This commit enhances resource to use
$http to encode any non-url parameters resulting in a query string like "/Path/doh?bar=baz1&bar=baz2".

BREAKING CHANGE: if the server relied on the buggy behavior then either the
backend should be fixed or a simple serialization of the array should be done
on the client before calling the resource service.