sync per mods, version.h and dockerfile to 2.1.6

docker/Dockerfile

-# Dockerfile for binary_c (2.1.5) and binary_grid2 (2.1.5)
+# Dockerfile for binary_c (2.1.6) and binary_grid2 (2.1.6)
 # based on Ubuntu 18.04
 
 FROM ubuntu:18.04
@@ -212,7 +212,7 @@ RUN cpanm Sort::Key
 RUN perl ./install_all.pl
 RUN cpanm Proc::ProcessTable
 RUN cpanm Cpanel::JSON::XS
-RUN cpanm -v ./binary_grid-v2.1.5.tar.gz
+RUN cpanm -v ./binary_grid-v2.1.6.tar.gz
 
 ############################################################
 # cleanup: cpanm and build directories

src/binary_c_version.h

@@ -30,7 +30,7 @@
  * 
  * Patch is zero for a major release.  
  */
-#define BINARY_C_VERSION "2.1.5"
+#define BINARY_C_VERSION "2.1.6"
 
 /* and a CEMP run version */
 #define CEMP_VERSION "prelim10-O1-noCNEMPs"