Tests: add test project

* manage.py file at the root of the project
* targetting the project located at tests/test_project/settings.py

That allows testing the linter through just calling it on the project itself.
Using the new method coming soon: `python manage.py lintmigrations`

tests/test_project/settings.py

@@ -0,0 +1,142 @@
+"""
+Django settings for test_project project.
+
+Generated by 'django-admin startproject' using Django 2.1.7.
+
+For more information on this file, see
+https://docs.djangoproject.com/en/2.1/topics/settings/
+
+For the full list of settings and their values, see
+https://docs.djangoproject.com/en/2.1/ref/settings/
+"""
+
+import os
+
+# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
+from collections import OrderedDict
+
+BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+
+
+# Quick-start development settings - unsuitable for production
+# See https://docs.djangoproject.com/en/2.1/howto/deployment/checklist/
+
+# SECURITY WARNING: keep the secret key used in production secret!
+SECRET_KEY = "dummy"
+
+# SECURITY WARNING: don't run with debug turned on in production!
+DEBUG = True
+
+ALLOWED_HOSTS = []
+
+
+# Application definition
+
+INSTALLED_APPS = [
+    "django.contrib.admin",
+    "django.contrib.auth",
+    "django.contrib.contenttypes",
+    "django.contrib.sessions",
+    "django.contrib.messages",
+    "django.contrib.staticfiles",
+    "django_migration_linter",
+    "tests.test_project.app_add_not_null_column",
+    "tests.test_project.app_add_not_null_column_followed_by_default",
+    "tests.test_project.app_alter_column",
+    "tests.test_project.app_correct",
+    "tests.test_project.app_create_table_with_not_null_column",
+    "tests.test_project.app_drop_column",
+    "tests.test_project.app_ignore_migration",
+    "tests.test_project.app_rename_column",
+    "tests.test_project.app_rename_table",
+]
+
+MIDDLEWARE = [
+    "django.middleware.security.SecurityMiddleware",
+    "django.contrib.sessions.middleware.SessionMiddleware",
+    "django.middleware.common.CommonMiddleware",
+    "django.middleware.csrf.CsrfViewMiddleware",
+    "django.contrib.auth.middleware.AuthenticationMiddleware",
+    "django.contrib.messages.middleware.MessageMiddleware",
+    "django.middleware.clickjacking.XFrameOptionsMiddleware",
+]
+
+ROOT_URLCONF = "tests.test_project.urls"
+
+TEMPLATES = [
+    {
+        "BACKEND": "django.template.backends.django.DjangoTemplates",
+        "DIRS": [],
+        "APP_DIRS": True,
+        "OPTIONS": {
+            "context_processors": [
+                "django.template.context_processors.debug",
+                "django.template.context_processors.request",
+                "django.contrib.auth.context_processors.auth",
+                "django.contrib.messages.context_processors.messages",
+            ]
+        },
+    }
+]
+
+WSGI_APPLICATION = "tests.test_project.wsgi.application"
+
+
+DATABASES = {
+    "default": {
+        "ENGINE": "django.db.backends.sqlite3",
+        "NAME": os.path.join(BASE_DIR, "db.sqlite3"),
+        "TEST": {"DEPENDENCIES": []},
+    },
+    "sqlite": {
+        "ENGINE": "django.db.backends.sqlite3",
+        "NAME": "sqlite3",
+        "TEST": {"DEPENDENCIES": []},
+    },
+    "postgresql": {
+        "ENGINE": "django.db.backends.postgresql",
+        "NAME": "django_migration_linter_test_project",
+        "USER": "postgres",
+        "TEST": {"DEPENDENCIES": []},
+    },
+    "mysql": {
+        "ENGINE": "django.db.backends.mysql",
+        "NAME": "django_migration_linter_test_project",
+        "USER": "travis",
+        "PASSWORD": "",
+        "HOST": "127.0.0.1",
+        "TEST": {"DEPENDENCIES": []},
+    },
+}
+
+
+# Password validation
+
+AUTH_PASSWORD_VALIDATORS = [
+    {
+        "NAME": "django.contrib.auth.password_validation.UserAttributeSimilarityValidator"
+    },
+    {"NAME": "django.contrib.auth.password_validation.MinimumLengthValidator"},
+    {"NAME": "django.contrib.auth.password_validation.CommonPasswordValidator"},
+    {"NAME": "django.contrib.auth.password_validation.NumericPasswordValidator"},
+]
+
+
+# Internationalization
+# https://docs.djangoproject.com/en/2.1/topics/i18n/
+
+LANGUAGE_CODE = "en-us"
+
+TIME_ZONE = "UTC"
+
+USE_I18N = True
+
+USE_L10N = True
+
+USE_TZ = True
+
+
+# Static files (CSS, JavaScript, Images)
+# https://docs.djangoproject.com/en/2.1/howto/static-files/
+
+STATIC_URL = "/static/"