API and build change and fix summaries. Doc correctsions
and/or changes are not mentioned here; see the commit messages.
+2019 November 13; version 1.12.1
+ New message type constants added to support A1.
+
+2019 November 7; version 1.12.0
+ Version cut to support continued development for next release
+ preserving the 1.11.* versions for release 1 (Amber) and
+ related fixes.
+
2019 October 31; version 1.10.2
Provide the means to increase the payload size of a received message
without losing the data needed to use the rmr_rts_msg() funciton.