Peter M. Groen / libmodbus

If the autoreconf program does not succeed, autogen.sh
should not succeed either.

The definition of "succeed" being "exit with exit code 0".

- remove doc build from autotools
- don't depend anymore on asciidoc
- don't provide man pages anymore
- new illustrations
- provide mkdocs instructions

- allocate exact memory required to store node and service strings
  instead of around 1kb of static memory.
- accept NULL value of service to use default Modbus port number (502)
- unit test updated

The new documentation will be updated in another commit.

Even the newest visual studio use /VERSION:major[.minor]  .  
It means link.exe  /VERSION:1.0  just  need two version number .
If Version = 1.0.0 , when visual studio  link the program , vs will produce link error:

```
1>"/OUT:C:\Users\Lenovo\Desktop\libmodbus-master\src\win32\modbus.dll" "/VERSION:1.0.0" /INCREMENTAL:NO /NOLOGO ws2_32.lib kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /MANIFEST "/MANIFESTUAC:level='asInvoker' uiAccess='false'" /manifest:embed /DEBUG "/PDB:C:\Users\Lenovo\Desktop\libmodbus-master\src\win32\modbus.pdb" /MAP /SUBSYSTEM:CONSOLE /TLBID:1 "/IMPLIB:C:\Users\Lenovo\Desktop\libmodbus-master\src\win32\modbus.lib" /MACHINE:X86 /SAFESEH /DLL "C:\Users\Lenovo\Desktop\libmodbus-master\src\win32\/modbus.res"
1>"Debug\modbus-data.obj"
1>"Debug\modbus-rtu.obj"
1>"Debug\modbus-tcp.obj"
1>Debug\modbus.obj
1>LINK : fatal error LNK1117: option“VERSION:1.0.0” grammatical error
```
see: 
https://docs.microsoft.com/en-us/cpp/build/reference/version-version-information?view=msvc-160

Address check in single register / coil responses added

According to Modbus standard the address of single register / coils request and response must match

Co-authored-by: Heinrich Gsponer <heinrich.gsponer@siemens.com>

It converts float values depending on what order they come in.

This patch was modified from rm5248 [1]

[1] https://github.com/synexxus/libmodbus/commit/a511768e7fe7ec52d7bae1d9ae04e33f87a59627

This native libmodbus error code is defined but not used.

Thank you @peternewman.

Sorry for the two PRs, I did one then realized I should check the other

While handling MODBUS_FC_WRITE_AND_READ_REGISTERS, both address offsets
must be checked, i.e. the read and the write address must be within the
mapping range.

At the moment, only the read address was considered, it looks like a
simple copy and paste error, so let's fix it.

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