Fix for bug13502  Some invalid URLs (e.g. those with spaces in) are no longer supported in hyperlinks

Use the long form of java.net.URI constructor that quotes the path component of a URI string containing reserved characters (in the sense of RFC 2396).

This allows a user to specify an external link with the [[...]] syntax that contains a space character (for example).

https://bugs.corefiling.com/show_bug.cgi?id=13502