- Mb2hal now uses libmodbus3 instead of the old libmodbus file
  located in src/hal/user_comps/modbus.c used by gs2_vfd.c
  # Also fix a TIMEOUT bug (due to this unpatched old libmodbus file).
- Better INI file documentation (HOW-TO).
- Better Submakefile.
- Source code cleaned and reordered.
  # Now is posible to add new functionallity.

See LogBook.txt for more information.

Signed-off-by: Michael Haberler <git@mah.priv.at>

Nothing big, two instances of dead initialization (so, a variable is
explicitly set at define-time, but then written to again before being read).

Signed-off-by: Sebastian Kuzminsky <seb@highlab.com>

This reverts commit ca835b429478324639df779e26005ca43b8917d1.

Victor says it is needed.

Userspace HAL component to communicate with one or
more Modbus devices.

Tests:
- TCP some functions = Remote IO Delta RTU-EN01,
  24 inputs, 8 outputs.
- RS232 some functions = Servo Drive Delta ASDA-B (1021-A 1Kw).
- TCP all functions = MoD_RsSim V8.20 (www.plcsimulator.org)
  on Windows XP SP3.

Signed-off-by: Michael Haberler <git@mah.priv.at>