Peter M. Groen / libmodbus

Add standalone Makefiles for the modbus DLL and tests, using the modbus DLL.

Thanks to Bill Gray.

Thanks to Denis Davydov

Fix EXXX values defined in Microsoft C Runtime 10

Thanks to Carlos Tangerino

Thanks to oldfaber

Thanks to oldfaber.

Original patch provided by Michael Haberler <git@mah.priv.at>.

Thanks again to Stefan Finzel.
It would be nice to run Valgrind more often...

Thanks to Stefan Finzel for the bug report

Signed-off-by: Michael Heimpold <mhei@heimpold.de>

Thanks to Thomas Stalder and Torello Querci for the report.

Original patch for new connect function by Thomas Stalder.