Sitemap fix progress

This addresses these sub-issues: 
Make sure you can drag over parent of child to duplicate on current level (seems to be last sibling problem). 
Make sure you can drag over homepage
Delete functionality seems like it’s screwing up after a page reloads or something? Delete stuff and edit stuff multiple times to see if it’s solid. 
Font awesome for icons

The hit areas are a still kind of narrow, and the cookie-ing for the system pages is still sticking after initially showing system pages, as I think it's reading responses as false and then the cookie is somehow always allowed to take precedence thereafter. Re: #225