Peter M. Groen / libmodbus

- protect against NULL IP address BTW
- update documentation

- allow an empty string or NULL for node argument
- protect against NULL in service argument
- new test for NULL service
- update documentation

Thanks to vgrin for the report

It's never too late to remove 261 lines of code ;)

Thanks to Marjan Tomas

Thank you Marjan Tomas.

Thanks to MarjanTomas.

Change API of function for libmodbus v3.2.0

Thanks to Perry Kundert for bug report and initial patches.

- add byte timeout tests (TCP backend only)
- update and improve documentation
- long timeout values are now uint32_t so it changes the API
  to disable byte timeout

POSIX-1.2001 for fd_set. Thanks to spider391Tang.

- update documentation
- 5 new tests
- updated NEWS file
- avoid include of time.h

It's strongly recommended to update your libmodbus library if you
use it in a slave/server application in a not trusted environment.

Debian package of libmodbus 3.0.4 already contains a patch to
mitigate the exploit but the patch isn't as strong than this one.

Add top build directory to tests. Otherwise modbus-version.h
won't be found during the build process.

Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>

Build fails with -Werror and -Wcast-align on ARMv5 platform

- depends of automake 1.11
- C99
- pic-only
- more warning C flags
- remove obscure checks
- don't print directories
- add libmodbus.pc to clean files
- remove -Werror

Thanks to Damian Zieliński.

Thanks to Denis Davydov