Added channel support to Marionette.d.ts

Marionette.d.ts includes definitions for Backbone.Wreqr, but does not support the recommended way of using the Wreqr object as seen here: https://github.com/marionettejs/backbone.marionette/blob/master/docs/marionette.application.md#accessing-the-global-channel

I've added the Channel object, and a definition to the Radio class as well. This is only a means of getting a specific channel through the channel() method, so while it is possible to create an instance of Radio, I've chosen only to include channel() method, and make it static.

This makes it possible to access the instance of a channel with the name 'global' like this (created if not found), as recommended in the above documentation: 
var channel = Backbone.Wreqr.radio.channel('global');
// channel.vent;

Finally, I've made the parameter context of the setHandler method in the Backbone.Wreqr.Handlers class optional, as this adheres to the actual implementation.
Made Wreqr.radio a module
add object path
 Underscore.js: Updated chained calls to first() so that they return a _ChainSingle<T> instead of _Chain<T>. This causes a future call to value() to return a single T rather than an array of T which matches underscore's behavior.
Add definitions for fingerprintjs
Merge pull request #2585 from zaneli/fingerprintjs

Add definitions for fingerprintjs
Merge pull request #2541 from Wordenskjold/master

Add channel support to backbone.wreqr in marionette.d.ts
Merge pull request #2586 from bomiller/underscore-chain-first

 Underscore.js: Fix for chained calls to first()
Update CONTRIBUTORS.md
Merge branch 'object-path' of github.com:pocesar/DefinitelyTyped into pocesar-object-path
Merge branch 'pocesar-ot push origin master:object-path'