fuzzing: Fuzz different print methods

This is achieved by encoding the type of function used in the first two
bytes.

First byte:
b: buffered

Second byte:
f: formatted

fuzzing/inputs/test1

@@ -1,4 +1,4 @@
-{
+bf{
     "glossary": {
         "title": "example glossary",
 		"GlossDiv": {