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-definition-package/index.js

@@ -0,0 +1,89 @@
+var Package = require('dgeni').Package;
+var jsdocPackage = require('dgeni-packages/jsdoc');
+var nunjucksPackage = require('dgeni-packages/nunjucks');
+var typescriptPackage = require('../typescript-package');
+var gitPackage = require('dgeni-packages/git');
+var path = require('canonical-path');
+
+// Define the dgeni package for generating the docs
+module.exports = new Package('angular-v2-docs', [jsdocPackage, nunjucksPackage, typescriptPackage, gitPackage])
+
+// Register the processors
+.processor(require('./processors/createTypeDefinitionFile'))
+
+.config(function(readFilesProcessor, inlineTagProcessor) {
+  readFilesProcessor.basePath = path.resolve(__dirname, '../..');
+  // Don't run unwanted processors
+  readFilesProcessor.$enabled = false;
+  inlineTagProcessor.$enabled = false;
+})
+
+
+// Configure the log service
+.config(function(log) {
+  log.level = 'info';
+})
+
+
+.config(function(renderDocsProcessor, versionInfo) {
+  renderDocsProcessor.extraData.versionInfo = versionInfo;
+})
+
+.config(function(readFilesProcessor, inlineTagProcessor, readTypeScriptModules) {
+
+  // Don't run unwanted processors
+  readFilesProcessor.$enabled = false; // We are not using the normal file reading processor
+  inlineTagProcessor.$enabled = false; // We are not actually processing the inline link tags
+
+  // Configure file reading
+  readFilesProcessor.basePath = path.resolve(__dirname, '../..');
+  readTypeScriptModules.sourceFiles = [
+    'angular2/angular2.ts',
+    'angular2/router.ts'
+  ];
+  readTypeScriptModules.basePath = path.resolve(path.resolve(__dirname, '../../modules'));
+})
+
+
+.config(function(parseTagsProcessor, getInjectables) {
+  parseTagsProcessor.tagDefinitions.push(require('./tag-defs/public'));
+  parseTagsProcessor.tagDefinitions.push(require('./tag-defs/private'));
+  parseTagsProcessor.tagDefinitions.push(require('./tag-defs/exportedAs'));
+
+  // We actually don't want to parse param docs in this package as we are getting the data out using TS
+  parseTagsProcessor.tagDefinitions.forEach(function(tagDef) {
+    if (tagDef.name === 'param') {
+      tagDef.docProperty = 'paramData';
+      tagDef.transforms = [];
+    }
+  });
+
+})
+
+
+// Configure file writing
+.config(function(writeFilesProcessor) {
+  writeFilesProcessor.outputFolder  = 'dist/docs';
+})
+
+
+// Configure rendering
+.config(function(templateFinder, templateEngine) {
+
+  // Nunjucks and Angular conflict in their template bindings so change Nunjucks
+  templateEngine.config.tags = {
+    variableStart: '{$',
+    variableEnd: '$}'
+  };
+
+  templateFinder.templateFolders
+      .unshift(path.resolve(__dirname, 'templates'));
+
+  templateFinder.templatePatterns = [
+    '${ doc.template }',
+    '${ doc.id }.${ doc.docType }.template.html',
+    '${ doc.id }.template.html',
+    '${ doc.docType }.template.html',
+    'common.template.html'
+  ];
+});