CR-2174 AME-1913
Implemented a servlet filter to filter incoming requests and redirect them XUI based on the result of a new attribute openam-xui-interface-enabled.  Since OPENAM-2811 affects XUI and the ability to login, this filter is currently disabled by default on all installations and upgrades until OPENAM-2811 is fixed.

git-svn-id: https://svn.forgerock.org/openam/trunk/openam@6304 0f4defcf-c51a-4c67-9f44-6fb5eba73c5d