at the very least this should be logged to make sure the build can be reproduced/debugged. e.g.
```
if 'LMOD_CMD' in os.environ:
    self.cmd= os.getenv('LMOD_CMD')
    self.log.debug('Using LMOD_CMD %s from environment.' % self.cmd)
```
@boegel do we need to add this to the buildstats?