New encode feature allows direct writing of byte string value (#137)

New features for UsefulBuf and for QCBOREncode allows direct writing to the output buffer. For QCBOREncode, this is the direct writing of the value of a byte string. This allows it to be written in chunks or be the output buffer of some function like symmetric encryption.


* fix grammer in security policy

* Half-way start a encoding feature to write byte string values into output

* Add documentation for OpenBstr

* UsefulBuf_Advance mostly working and testing

* OpenBytes() is mostly working and somewhat tested

* Finish up OpenBytes -- error handing, documentation...

Co-authored-by: Laurence Lundblade <lgl@securitytheory.com>
diff --git a/test/UsefulBuf_Tests.h b/test/UsefulBuf_Tests.h
index 0d06206..235358e 100644
--- a/test/UsefulBuf_Tests.h
+++ b/test/UsefulBuf_Tests.h
@@ -50,4 +50,6 @@
 const char *  UBUTest_CopyUtil(void);
 #endif /* USEFULBUF_DISABLE_ALL_FLOAT */
 
+const char * UBAdvanceTest(void);
+
 #endif