[SEBA-512]

Fix xosgenx's handling of optional/required modifiers in relation to
the null and blank options, which was nondeterministic depending on the
order of items iterated over in the options dictionary.

Don't allow 'Null' booleans

Change-Id: I3f21180ec11c7e43794c04ebe479d50c11f6271c
diff --git a/VERSION b/VERSION
index 5859406..530cdd9 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.2.3
+2.2.4