Generate single header even if output dir does not exist
diff --git a/scripts/generateSingleHeader.py b/scripts/generateSingleHeader.py
index 18a2612..bef63b0 100755
--- a/scripts/generateSingleHeader.py
+++ b/scripts/generateSingleHeader.py
@@ -36,6 +36,8 @@
         print( "\n** Unrecognised argument: " + arg + " **\n" )
         exit(1)
 
+# ensure that the output directory exists
+os.makedirs(os.path.dirname(outputPath), exist_ok = True)
 out = open( outputPath, 'w' )
 ifdefs = 0
 implIfDefs = -1