We have a situation, when we have DWG_VERSION_TYPE definitions in include/dwg.h, but this is related to DWG file, not to AutoCAD release.

Intent behind this is, that we need to define AutoCAD version and set defaults related to AutoCAD version.
e.g.
We have AutoCAD R_13 and AutoCAD R_2000.  Boths could encode DWG file to AC1012 version.
But result is different e.g. in case of sections. This is common problem.
AutoCAD R_13:
```
num_sections: 3 [RL]
num_sections => 3
section[0].number:         0 [RC] AcDb:Header
section[0].address:       70 [RL]
section[0].size:         454 [RL]
section[1].number:         1 [RC] AcDb:Classes
section[1].address:      524 [RL]
section[1].size:          38 [RL]
section[2].number:         2 [RC] AcDb:Handles
section[2].address:     3977 [RL]
section[2].size:          79 [RL]
crc: A24C [RSx] from 0-52
         HEADER (end):      70
```

AutoCAD R_2000:
```
num_sections: 5 [RL]
num_sections => 5
section[0].number:         0 [RC] AcDb:Header
section[0].address:    18207 [RL]
section[0].size:         484 [RL]
section[1].number:         1 [RC] AcDb:Classes
section[1].address:    18691 [RL]
section[1].size:         475 [RL]
section[2].number:         2 [RC] AcDb:Handles
section[2].address:    25375 [RL]
section[2].size:         273 [RL]
section[3].number:         3 [RC] AcDb:ObjFreeSpace
section[3].address:    25648 [RL]
section[3].size:          53 [RL]
section[4].number:         4 [RC] AcDb:Template
section[4].address:    25847 [RL]
section[4].size:           4 [RL]
crc: DA60 [RSx] from 0-70
         HEADER (end):      88
```
Define AutoCAD release versions in include/dwg.h
This is a GitHub Issue
repo:libredwg
owner:LibreDWG
Title : Define AutoCAD release versions in include/dwg.h
Issue date:

--- start body ---
We have a situation, when we have DWG_VERSION_TYPE definitions in include/dwg.h, but this is related to DWG file, not to AutoCAD release.

Intent behind this is, that we need to define AutoCAD version and set defaults related to AutoCAD version.
e.g.
We have AutoCAD R_13 and AutoCAD R_2000.  Boths could encode DWG file to AC1012 version.
But result is different e.g. in case of sections. This is common problem.
AutoCAD R_13:
```
num_sections: 3 [RL]
num_sections => 3
section[0].number:         0 [RC] AcDb:Header
section[0].address:       70 [RL]
section[0].size:         454 [RL]
section[1].number:         1 [RC] AcDb:Classes
section[1].address:      524 [RL]
section[1].size:          38 [RL]
section[2].number:         2 [RC] AcDb:Handles
section[2].address:     3977 [RL]
section[2].size:          79 [RL]
crc: A24C [RSx] from 0-52
         HEADER (end):      70
```

AutoCAD R_2000:
```
num_sections: 5 [RL]
num_sections => 5
section[0].number:         0 [RC] AcDb:Header
section[0].address:    18207 [RL]
section[0].size:         484 [RL]
section[1].number:         1 [RC] AcDb:Classes
section[1].address:    18691 [RL]
section[1].size:         475 [RL]
section[2].number:         2 [RC] AcDb:Handles
section[2].address:    25375 [RL]
section[2].size:         273 [RL]
section[3].number:         3 [RC] AcDb:ObjFreeSpace
section[3].address:    25648 [RL]
section[3].size:          53 [RL]
section[4].number:         4 [RC] AcDb:Template
section[4].address:    25847 [RL]
section[4].size:           4 [RL]
crc: DA60 [RSx] from 0-70
         HEADER (end):      88
```
--- end body ---
