Fixed two problems when running/testing fcrepo4 on Windows

In Windows ':' is a reserved character, so when checking out this project one ends up with a file named "nt" instead of "nt:folder.vsl". Therefore the names were changed to contain a dash instead of a colon. In HtmlProvider a simple replace(char,char) is added to the template map entry generation in order to successfully lookup the a template "nt-folder.vsl" from a nodetype "nt:folder"