finalizing things for version 2.1

configure.ac

 dnl Process this file with autoconf to produce a configure script.
 
 AC_PREREQ([2.69])
-AC_INIT([rock],[2.0])
+AC_INIT([rock],[2.1])
 
 
 AC_CANONICAL_TARGET

src/ROCKparams.cpp

@@ -41,7 +41,7 @@ const int ROCKparams::undef_ext;
 
 void usage(int status) {
 	cout<<endl;
-	cout<<"ROCK 2.0                    Copyright (C) 2016-2022 Institut Pasteur"<<endl;
+	cout<<"ROCK 2.1                    Copyright (C) 2016-2022 Institut Pasteur"<<endl;
 	cout<<endl;
 	cout<<"Reducing Over-Covering K-mers within FASTQ file(s)"<<endl;
 	cout<<endl;