[BUG] `logs` folder should be named `log`

[adamretter]

All but one folder in an exist distribution are named in the singular e.g. autodeploy, bin, etc, and lib.

Unfortunately the folder for log files is named in the plural, i.e.: logs. It should have been named log, which would be inline with the LFS standard of names such as /var/lib and /var/log.

This is a breaking change, so needs to wait for a major release.

[duncdrum]

see eXist-db/documentation#230

[line-o]

I am in favour of this change. I would not call it a bug, personally.