msh: create testsuite (based on hush one)
hush: add TODO (doesn't know ":" command)

diff --git a/shell/msh_test/msh-parsing/argv0.tests b/shell/msh_test/msh-parsing/argv0.tests
new file mode 100755
index 0000000..f5c40f6
--- /dev/null
+++ b/shell/msh_test/msh-parsing/argv0.tests
@@ -0,0 +1,4 @@
+if test $# = 0; then
+    exec "$THIS_SH" "$0" arg
+fi
+echo OK