Fix FSharp.Reactive to work with VS2013
Merge pull request #12 from forki/master

Fix FSharp.Reactive to work with VS2013
Update package references to Rx 2.2.2.
Merge pull request #15 from jack-pappas/rx-2.2.2

Update package references to Rx 2.2.2.
The definition of Observable.zip is incorrect as it should allow the first observable to be of a different type to the second observable
Merge pull request #18 from andybrackley/master

The definition of Observable.zip is incorrect as it should allow the fir...