'templates', 'router', 'url', and method override

added 'templates' setting to tell phtml() where to find phtml files
added 'router' to tell dispatch() to strip the routing file from the uri
added 'url' to allow running dispatch() from a sub path (ie, /my-apps/)
added support for method override via header or _method, only for POST
all configuration settings are optional
fixes #57, #58