mwrefs should register mediawiki-utilities as a dependency

[harej]

I installed mwrefs via pip and then tried to use it:

Norepinephrine:scripts jh$ mwrefs extract -h
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/mwcli/router.py", line 49, in main
    package=self.package_name)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 978, in _gcd_import
  File "<frozen importlib._bootstrap>", line 961, in _find_and_load
  File "<frozen importlib._bootstrap>", line 950, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 655, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 205, in _call_with_frames_removed
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/mwrefs/utilities/extract.py", line 24, in <module>
    from mw import xml_dump
ModuleNotFoundError: No module named 'mw'
Could not load utility extract.

Then after installing mediawiki-utilities...

Norepinephrine:scripts jh$ mwrefs extract -h
Extracts reference tags from Wikipedia XML database dumps.

Generates a TSV dataset with one row per revision with the following fields.

* page_id
* page_title
* rev_id
* rev_timestamp
* ref_tag

Usage:
    extract -h | --help
    extract <dump-file>...

Options:
    -h --help    Prints this documentation
    <dump-file>  Path to a set of XML dumps files (pages meta history)
Norepinephrine:scripts jh$ 

This leads me to believe that mediawiki-utilities is not properly registered as a dependency in mwrefs.

[halfak]

Right. This should switch entirely over to using mwxml rather than mediawiki-utilities.