Filter update

The following files contain filter updates. The files expand into a .KERNELS directory which should be copied to $HOME/.KERNELS. It is not necessary to download all updates, the latest update contains all predecessors.

Update November 11th, 2002 for Xenomorph 0.2 and later, includes MSD (mean squared differences) filters.
Update November 27th, 2002 for Xenomorph 0.2 and later, includes direction opening and closing operators.
Update July 21th, 2004 for Xenomorph 0.6 and later, introduces midrange filters and filters to select small structures without selecting edges