ash: add most of hush process subst tests

ash passes these.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/ash_test/ash-psubst/tick2.tests b/shell/ash_test/ash-psubst/tick2.tests
new file mode 100755
index 0000000..db4e944
--- /dev/null
+++ b/shell/ash_test/ash-psubst/tick2.tests
@@ -0,0 +1,5 @@
+if false; then
+    echo "FOO"
+    tmp=`echo BAR >&2`
+fi
+echo BAZ