Peter M. Groen / libmodbus

The library is now simpler to include (only one <modbus.h>)
To avoid confusion MB_VERSION defines have been renamed to
LIBMODBUS_VERSION.

This reverts commit df0cf7927249954f15e0aa85b02d21b990fa9af9.
Use <modbus.h> in tests.

- returns -1 on error and set errno
- error recovery system was flawed
- error recovery disabled by default
- remove a malloc

Some files reference modbus.pc or modbus.pc.in while other files
reference libmodbus.pc or libmodbus.pc.in.

Let stick with libmodbus.pc or libmodbus.pc.in.

Inspired by the Clutter project and work done by Florian Forster.

This time the change is definitive :)

Avoid to create generic INSTALL file

I don't want to put a burden on build system support anymore

Requests not to send SIGPIPE on errors on stream oriented sockets
when the other end breaks the connection.

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

The previous implementation dereferenced a type-puned pointer, which is
illegal according to ANSI C. Some newer versions of GCC will complain
about this. This implementation uses "memcpy" to avoid this problem.

- the return value is used to pass the message length
- remove the hack on exception check in modbus receive
- update tests

It occurs on first occurence of slave timeout (found with Valgrind 3.3.0).
Reported by Henrik Munktell.

- simpler wscript_build files
- reuse VERSION
- add path to config.h

Reported by Henrik Munktell.

They came with autoconf-2.59, which does not support AC_TYPE_UINT*_T .

- removed maintainer-mode
- RANLIB useless

- adjusts various comments on return values
- updated tests
- added entry to MIGRATION