Added PartCategory

- Parent can be null (top-level category)
- Parent can be other PartCategory

.gitignore

@@ -3,9 +3,6 @@ __pycache__/
 *.py[cod]
 *$py.class
 
-# C extensions
-*.so
-
 # Distribution / packaging
 .Python
 env/
@@ -24,66 +21,9 @@ var/
 .installed.cfg
 *.egg
 
-# PyInstaller
-#  Usually these files are written by a python script from a template
-#  before PyInstaller builds the exe, so as to inject date/other infos into it.
-*.manifest
-*.spec
-
-# Installer logs
-pip-log.txt
-pip-delete-this-directory.txt
-
-# Unit test / coverage reports
-htmlcov/
-.tox/
-.coverage
-.coverage.*
-.cache
-nosetests.xml
-coverage.xml
-*,cover
-.hypothesis/
-
-# Translations
-*.mo
-*.pot
 
 # Django stuff:
 *.log
 local_settings.py
-
-# Flask stuff:
-instance/
-.webassets-cache
-
-# Scrapy stuff:
-.scrapy
-
-# Sphinx documentation
-docs/_build/
-
-# PyBuilder
-target/
-
-# IPython Notebook
-.ipynb_checkpoints
-
-# pyenv
-.python-version
-
-# celery beat schedule file
-celerybeat-schedule
-
-# dotenv
-.env
-
-# virtualenv
-venv/
-ENV/
-
-# Spyder project settings
-.spyderproject
-
-# Rope project settings
-.ropeproject
+*.sqlite3
+**/migrations/*