Moved legacy code into archive, ready for a new rapid(?) prototype.

I may regret doing this!

unit-tests/nil.sh

@@ -1,13 +0,0 @@
-#!/bin/bash
-
-expected=nil
-actual=`echo 'nil' | target/psse 2>/dev/null | tail -1`
-
-if [ "${expected}" = "${actual}" ]
-then
-    echo "OK"
-    exit 0
-else
-    echo "Fail: expected '${expected}', got '${actual}'"
-    exit 1
-fi