- Added method to Glottolog API to retrieve language-level languoids, e.g.
to supplement coordinates for dialects.
- Bugfix: Handle multi-line citations properly when creating README.md
- Drop Python 3.7 compatibility.
Backwards incompatibility
`DataDir.download` treated its `fname` argument inconsistently. This is
fixed now, resulting in changed behaviour when `fname` was of type `str` and
contained a `/`. In this case, `fname` is now assumed to be an absolute
path or a path relative to `cwd` and **not** relative to the `DataDir` instance.
Thus, `DataDir.download` now interprets `fname` in the same way as all other
`DataDir` methods accepting a `fname` argument.