A bunch of fixes to express declaration

- Move Express-prefixed interface names into internal module as
  unprefixed names
- The importing code will use express.Response instead of
  ExpressServerResponse
- Internal definitions can just use Response instead of
  ExpressServerResponse
- Response should extend http.Response to be able to type check .end
  for example
Added Observable.zip() which was missing.

https://github.com/Reactive-Extensions/RxJS/blob/master/doc/api/core/observable.md#rxobservablezipargs
Changed Observable.zip<TResult>(...) to Observable.zip<T>(...)
Merge pull request #1261 from vegemite4me/master

Added Observable.zip() which was missing.
Merge pull request #1077 from sgronblo/improve_express_d_ts

Namespacing for express definition
Update requested definitions to just be a link
Tightened up ValidationOptions

Using a combination of the source code and the documentation at
http://jqueryvalidation.org/validate/ I've tightened up the
ValidationOptions.  NB success remains as any because (AFAIK) it's not
possible to model alternate overloads in an interface with TypeScript (
https://typescript.codeplex.com/workitem/1893 ).
Merge pull request #1270 from johnnyreilly/master

jQuery Validation: Tightened up ValidationOptions