Changed default value of BaseUrl pin in The HTMLTexture (EX9.Texture String) node .

* New default is empty string in which case the node will use the local patch path as base URL.
* The node will also append a trailing slash to base URLs using the file:// scheme as described here: http://vvvv.org/forum-alpha/64bit-htmltexture%28string%29-relative-local-paths-command-lines