Bump version number to 3.1.0 and library version

configure.ac

@@ -12,8 +12,8 @@
 # http://www.gnu.org/software/libtool/manual/html_node/Libtool-versioning.html
 #
 m4_define([libmodbus_version_major], [3])
-m4_define([libmodbus_version_minor], [0])
-m4_define([libmodbus_version_micro], [1])
+m4_define([libmodbus_version_minor], [1])
+m4_define([libmodbus_version_micro], [0])
 
 m4_define([libmodbus_release_status],
     [m4_if(m4_eval(libmodbus_version_minor % 2), [1], [snapshot], [release])])
@@ -40,9 +40,9 @@ AC_SUBST(LIBMODBUS_VERSION)
 
 # ABI version
 # http://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
-LIBMODBUS_LD_CURRENT=5
+LIBMODBUS_LD_CURRENT=6
 LIBMODBUS_LD_REVISION=0
-LIBMODBUS_LD_AGE=0
+LIBMODBUS_LD_AGE=1
 LIBMODBUS_LT_VERSION_INFO=$LIBMODBUS_LD_CURRENT:$LIBMODBUS_LD_REVISION:$LIBMODBUS_LD_AGE
 AC_SUBST(LIBMODBUS_LT_VERSION_INFO)