Include some minor fixes from my fork

[GiscardBiamby]

• Fix javascript error in dashboard
• Fix bug that allows invalid values for "priority" if you don't set .Priority in custom ISitemapRouteProvider (did this and got validation errors in google webmaster tools; this fix resolved the error)

[GiscardBiamby]

Done! Glad you are accepting the fixes. It's a useful module, and the ability to provide custom url's via implementing an interface is great, it's the main reason I ended up using this.

Though, it was hard to figure out how the display /sitemap was being organized, and why some of my custom routes weren't showing up. Something about the way this module organizes everything according to the url path folders (/mainfolder/subfolder1/subfolder2/etc), using the folders as levels. I never got it to work with my custom routes but I worked around it by creating a series of alphabetical index pages that linked to all the custom routes. I used these alpha index pages in the display sitemap instead of all the custom content, and that worked.

Suggestions for improvement:

1. Provide better documentation on how the module organizes the content, and how you need to structure your URL's to work with the module (or, alternatively, how you can override the module's rules for this)
2. Support for providing customized organizations, rather than the default one. Probably pretty complicated though, and lower priority, because people can just implement their own sitemap page once they need to do this.