Allow embedding of CSS in ejs head.
Update single image page
Add the initial section of the challenges site.

* Updated routes
   /challenge/create
   /challenge/view/#
   /challenge/edit/#
   /challenge/add
* Created challenge.js to hold code for making challenge pages.
* Created create-challenge.ejs for the page
* Created view-challenge.ejs for te page.
Remove junk code from challenge.js