updated AuthType & Require per shibboleth wiki

I noticed that I get ``.htaccess: Unknown Authz provider: Shibboleth`` using the .htaccess that is created so I checked the doc and it looks like it should be "shibboleth" instead "Shibboleth".

https://wiki.shibboleth.net/confluence/display/SHIB2/NativeSPApacheConfig#NativeSPApacheConfig-EnablingtheModuleforAuthentication