chore(doc-gen): put typescript stuff into its own package

This means that we can now run just the d.ts file generation by running:

```bash
gulp docs/typings
```

In addition the type definition generation was messing with the other docs tasks
so separating it also fixes problems there.

docs/typescript-package/mocks/mockPackage.js

@@ -0,0 +1,11 @@
+var Package = require('dgeni').Package;
+
+module.exports = function mockPackage() {
+
+  return new Package('mockPackage', [require('../')])
+
+  // provide a mock log service
+  .factory('log', function() { return require('dgeni/lib/mocks/log')(false); })
+  .factory('templateEngine', function() { return {}; });
+
+};

docs/typescript-package/mocks/readTypeScriptModules/ignoreExportsMatching.ts

@@ -0,0 +1,4 @@
+export var __esModule = true;
+export class OKToExport {}
+export function _thisIsPrivate() {}
+export var thisIsOK = '!';

docs/typescript-package/mocks/readTypeScriptModules/interfaces.ts

@@ -0,0 +1,5 @@
+export interface MyInterface {
+  optionalProperty? : string
+  <T, U extends Findable<T>>(param: T) : U
+  new (param: number) : MyInterface
+}

docs/typescript-package/mocks/readTypeScriptModules/orderingOfMembers.ts

@@ -0,0 +1,6 @@
+export class Test {
+  firstItem;
+  constructor() { this.doStuff(); }
+  otherMethod() {}
+  doStuff() {}
+}

docs/typescript-package/mocks/tsParser/importedSrc.ts

@@ -0,0 +1 @@
+export var x = 100;

docs/typescript-package/mocks/tsParser/testSrc.ts

@@ -0,0 +1,34 @@
+/**
+ * @module
+ * @description
+ * This is the module description
+ */
+
+export * from 'importedSrc';
+
+/**
+ * This is some random other comment
+ */
+
+/**
+ * This is MyClass
+ */
+export class MyClass {
+  message: String;
+
+  /**
+   * Create a new MyClass
+   * @param {String} name The name to say hello to
+   */
+  constructor(name) { this.message = 'hello ' + name; }
+
+  /**
+   * Return a greeting message
+   */
+  greet() { return this.message; }
+}
+
+/**
+ * An exported function
+ */
+export var myFn = (val: number) => return val * 2;