prevent call of success/failure handlers if timeout Fixes #2529997

remove jsonp-url from jsonp. Killing the rollup of jsonp-base and jsonp-url. Most use cases will be served by passing a function as a parameter. It's a rare case that the callback must be named in the url and the developer doesn't have control of this. If such is the case, they can use('jsonp-url') for the functionality. Otherwise, the majority gets the simpler module name 'jsonp'.

Simplify url callback parsing, Extract to submod. Split into jsonp-base and jsonp-url. Base does simple, single level name resolution for callback-in-url parsing (callback=foo, or callback=Y.foo). Nested parsing moved to jsonp-url (callback=foo.bar["baz"]).