Document upcoming API changes in README
The ACVP specification is a work-in-progress and can be found at
https://github.com/usnistgov/ACVP
+Upcoming Changes!
+
+ The library API has been updated as of **August 2018** to store hex buffers
+ as their equivalent byte arrays. This simplifies the responsibilities of
+ the applicatin layer as most C crypto libraries ingest/output byte
+ arrays by default. From now on, test case properties that show in the ACVP
+ spec as hex strings will be stored as byte arrays, and the library will
+ expect the application to populate result attributes as byte arrays as
+ well. For examples, see app/app_main.c.
+
Overview
