Update version number

Author: aursiber

DESCRIPTION

@@ -1,5 +1,5 @@
 Package: nlstools
-Version: 2.1-0
+Version: 2.1.1
 Title: Tools for Nonlinear Regression Analysis
 Authors@R: c(person("Florent", "Baty", role = "aut", email = "florent.baty@gmail.com"),
              person("Marie-Laure", "Delignette-Muller", role = "aut", email = "marielaure.delignettemuller@vetagro-sup.fr"),