chore(README): Banner URL

Author: JamesHenry

README.md

@@ -12,6 +12,6 @@
 
 <br>
 <p align="center" style="border: 1px solid blue;">
-<a href="http://typescriptcourses.com" target="_blank"><img src="https://user-images.githubusercontent.com/900523/33187671-54d039fc-d08b-11e7-809b-b5b99b5a8a8f.png" alt="typescriptcourses.com"/></a>
+<a href="http://typescriptcourses.com" target="_blank"><img src="https://james-henry-cdn.firebaseapp.com/images/typescriptcourses-github-banner.png" alt="typescriptcourses.com"/></a>
 </p>
 <br>