adds sample .env file

Author: anselrognlie

.env.sample

@@ -0,0 +1,7 @@
+# connection strings for development and testing
+# often of the form
+# protocol+driver://user:password@host:port/db_name
+# such as
+# postgresql+psycopg2://postgres:postgres@localhost:5432/retro_video_store_development
+SQLALCHEMY_DATABASE_URI=development_connection_string
+SQLALCHEMY_TEST_DATABASE_URI=test_connection_string