Update readme and minimum Perl version info

Change-Id: I74b725badd180ca2bc1254caa80fead31bbd5c29
diff --git a/Makefile.PL b/Makefile.PL
index 9f28aaf..d2dca03 100644
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -1,4 +1,4 @@
-use 5.010001;
+use 5.016;
 use strict;
 use warnings;