Add coverage, set up CI.

.coveragerc

@@ -0,0 +1,14 @@
+[run]
+command_line = manage.py test
+
+branch = true
+
+source =
+    main/
+
+
+omit =
+    main/migrations/*
+    main/apps.py
+    main/tests.py
+

.gitlab-ci.yml

@@ -0,0 +1,23 @@
+image: python:3-alpine
+
+stages:
+  - test
+
+django_test:
+  stage: test
+  before_script:
+    - pip install -r requirements/dev.txt
+  script:
+    - python manage.py test
+
+coverage:
+  stage: test
+  before_script:
+    - pip install -r requirements/dev.txt
+  script:
+    - coverage run
+    - coverage report -m
+    - coverage html -d public/coverage
+  artifacts:
+    paths:
+      - public/coverage

requirements/dev.txt

@@ -7,3 +7,6 @@ sphinx-rtd-theme==0.5.2
 sphinx-autodoc-typehints==1.12.0
 pyenchant==3.2.0
 sphinxcontrib-spelling==7.2.1
+
+# Tests
+coverage==5.5