Fix wrong constant names to create version number

Thanks to Denis Davydov
Fix missing argument in synopsis section of modbus_rtu_set_serial_mode

Thanks to Bill Gray.
Fix compilation and execution of bandwidth tests in Windows.
Avoid to define closesocket on POSIX systems in tests
Add oldfaber to AUTHORS
Fix: CreateFile() does not set errno. Use GetLastError().
Fix the last warning with Visual Studio 2008.
Add Visual Studio 2008 project files.
Add standalone Makefiles for the modbus DLL and tests, using the modbus DLL.
Don't hardcode libmodbus version number in modbus.dll.manifest
Rename product name to libmodbus to avoid to use a registered name
More usual name for a README
Updated NEWS file
Add stamp-h2 to gitignore
Fix missing close on socket in random-test-server

Thanks to Damian Zieliński.
Add unit tests for modbus_mapping_new
Dynamic memory allocation of device name (closes #11)
Calculate RTS activation time by send length
Symlinks instead of copies in autogen.sh
Cleanup .gitignore
Add success message to autogen.sh