[master][5a0f5768] Strange map generation results

[TransshipmentEnvoy]

I get strange map generation results. The map and its generation settings are provided in the attachment.

The game is compiled on latest commit (5a0f5768) on master branch on a Linux machine.

[TransshipmentEnvoy]

The issue only appears on `cmake` builds.

It is related to option `SIMUTRANS_ENABLE_RANDOMNESS`. If set `-DSIMUTRANS_ENABLE_RANDOMNESS=ON` in cmake configuration, the map generation results are normal.

The option adds compile definition `DISABLE_RANDOMNESS` which affects random number generation in `simrandom.cc`.

[TransshipmentEnvoy]

The random number generator returns constant value if the range (`max`) is fixed.

```
#ifdef DISABLE_RANDOMNESS
   return max / 2;
```

[jamespetts]

That is interesting - it looks as though there is a problem with the default setting for the CMAKE build, in that the disable randomness preprocessor definition is only intended to be used for debugging, and randomness should be on by default.

[Roboron]

Easy solution then, let's the randomness reign by default!

=> https://github.com/jamespetts/simutrans-extended/pull/566

[jamespetts]

Thank you - now incorporated.