update readme

README.md

@@ -18,6 +18,7 @@ This project does depend on python packages.
 * [```pip install pywikibot```](https://pypi.org/project/pywikibot/)
 * [```pip install wikitextparser```](https://pypi.org/project/wikitextparser/)
 * [```pip install gitpython```](https://gitpython.readthedocs.io/en/stable/)
+* [```pip install sqlite3```](https://docs.python.org/3/library/sqlite3.html) Might be provided with python
 * [```pip install importlib```](https://pypi.org/project/importlib/)  
 _Optional (for python 2.*, not tested)_
 * run ``./setup.py`` (used to store wikstraktor version in wiktionary extracts)