Map sorting

* Checkpoint work on sorting and CDE

* sort seems to be working

* Complete testing and doc

* revert float stuff so this PR is only sorting

* Documentation and tidiness for UsefulOutBuf

* Final tidy-up of sorting doc and code

---------

Co-authored-by: Laurence Lundblade <lgl@securitytheory.com>
diff --git a/test/qcbor_encode_tests.h b/test/qcbor_encode_tests.h
index bac1085..5271fd4 100644
--- a/test/qcbor_encode_tests.h
+++ b/test/qcbor_encode_tests.h
@@ -1,6 +1,6 @@
 /*==============================================================================
  Copyright (c) 2016-2018, The Linux Foundation.
- Copyright (c) 2018-2022, Laurence Lundblade.
+ Copyright (c) 2018-2023, Laurence Lundblade.
  All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
@@ -192,5 +192,8 @@
 int32_t OpenCloseBytesTest(void);
 
 
+/* Test map sorting */
+int32_t SortMapTest(void);
+
 
 #endif /* defined(__QCBOR__qcbor_encode_tests__) */