Updated configure.ac with silent rules

- run autoupdate
- remove some warnings
- enable silent rules
- bump the version to 2.1.0

configure.ac

@@ -1,18 +1,19 @@
 #                                               -*- Autoconf -*-
 # Process this file with autoconf to produce a configure script.
 
-AC_PREREQ(2.59)
-AC_INIT(libmodbus, 2.0.3, stephane.raimbault@gmail.com)
+AC_PREREQ(2.63)
+AC_INIT([libmodbus],[2.1.0],[stephane.raimbault@gmail.com])
 AC_CONFIG_SRCDIR([src/modbus.c])
 AC_CONFIG_HEADERS([config.h])
-AM_INIT_AUTOMAKE
-AM_DISABLE_STATIC
+AM_INIT_AUTOMAKE([1.11])
+# enable nice build output on automake1.11
+m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])])
 
 # Checks for programs.
 AC_PROG_CC
 AC_PROG_CXX
 AC_PROG_MAKE_SET
-AC_PROG_LIBTOOL
+LT_INIT([disable-static])
 
 # Checks for header files.
 AC_HEADER_STDC
@@ -33,13 +34,12 @@ AC_CHECK_DECLS([__CYGWIN__])
 
 # Checks for library functions.
 AC_FUNC_FORK
-AC_FUNC_SELECT_ARGTYPES
-AC_TYPE_SIGNAL
 AC_CHECK_FUNCS([gettimeofday inet_ntoa memset select socket strerror])
 
-AC_OUTPUT([
+AC_CONFIG_FILES([
         Makefile
         src/Makefile
         tests/Makefile
         modbus.pc
 ])
+AC_OUTPUT