Remove psycopg2 from dependencies (#117)

* remove psycopg2 from direct dependencies, only add it in tests

* bump to 1.0.1

* fix mypy

mypy_django_plugin/django/context.py

@@ -3,7 +3,6 @@ from collections import defaultdict
 from contextlib import contextmanager
 from typing import TYPE_CHECKING, Dict, Iterator, List, Optional, Tuple, Type
 
-from django.contrib.postgres.fields import ArrayField
 from django.core.exceptions import FieldError
 from django.db.models.base import Model
 from django.db.models.fields import AutoField, CharField, Field
@@ -18,6 +17,12 @@ from mypy.types import TypeOfAny
 
 from mypy_django_plugin.lib import helpers
 
+try:
+    from django.contrib.postgres.fields import ArrayField
+except ImportError:
+    class ArrayField:  # type: ignore
+        pass
+
 if TYPE_CHECKING:
     from django.apps.registry import Apps  # noqa: F401
     from django.conf import LazySettings  # noqa: F401