+2020 February 6; version 3.1.2
+ Fix disconnection detection bug in interface to SI95.
+
+2020 January 31; verison 3.1.1
+ Allow route table thread logging to be completely disabled
+ when logging is turned off.
+
+2020 January 26; verison 3.1.0
+ First step to allowing the user programme to control messages
+ written to standard error. Introduces the rmr_set_vlevel()
+ function, and related environment variable.
+