Update Views/Admin/Cache.cshtml

Fixed incorrect form action.
Update Extensions/StringExtensions.cs

Made extension methods more resilient to null & empty slugs.
Update Services/AdvancedSitemapService.cs

Allow custom route to be specified for the root path (eg. To allow priority to be increased on the home page)
Update Services/AdvancedSitemapService.cs

Improve linking and titles in display mode and in the admin display layout screen.
Update Views/Sitemap.Group.cshtml

Ensure link is correctly generated for homepage (root path) in display mode.
Update Providers/ISitemapRouteProvider.cs

Added support for over-riding content routes with custom routes. This allows certain pages to have the priority increased or decreased as required.
Update Providers/Impl/ContentRouteProvider.cs

Added support for over-riding content routes with custom routes. This allows certain pages to have the priority increased or decreased as required.
Update Providers/Impl/CustomRouteProvider.cs

Added support for over-riding content routes with custom routes. This allows certain pages to have the priority increased or decreased as required.
Update Controllers/HomeController.cs

Added support for over-riding content routes with custom routes. This allows certain pages to have the priority increased or decreased as required.
Merge pull request #11 from mjy78/master

Allow greater control for xml output and fix bugs with display output