support FLASK_ENV='testing'

Author: usrbinsam

application.py

@@ -6,10 +6,12 @@
 
 from CodeChallenge import create_app
 
-FLASK_ENV = os.environ.get("FLASK_ENV")
+FLASK_ENV = os.getenv("FLASK_ENV")
 
-if FLASK_ENV and FLASK_ENV == "development":
+if FLASK_ENV == "development":
     cfg = "DevelopmentConfig"
+elif FLASK_ENV == "testing":
+    cfg = "TestingConfig"
 else:
     cfg = "ProductionConfig"