Update TypeScript documentation (2.9.0)

lib/docs/scrapers/typescript.rb

@@ -2,7 +2,7 @@ module Docs
   class Typescript < UrlScraper
     self.name = 'TypeScript'
     self.type = 'typescript'
-    self.release = '2.8.3'
+    self.release = '2.9.0'
     self.base_url = 'https://www.typescriptlang.org/docs/'
     self.root_path = 'tutorial.html'
     self.links = {