large refactor of code to use venv (in .python) for DEV, to use consistent python versions with PROD, sepcifically flask 2.2.2 to address the deprecation of FLASK_ENV -> replaced with ENV. Fixed up git and dockerignores to be more stringent

files.py

@@ -726,7 +726,7 @@ def view(id):
     if id not in eids:
         print( f"ERROR: viewing an id, but its not in eids OPT={OPT}, id={id}, eids={eids}")
         msg="Sorry, viewing data is confused, cannot view this image now"
-        if os.environ['FLASK_ENV'] == "production":
+        if os.environ['ENV'] == "production":
             msg += "Clearing out all states.  This means browser back buttons will not work, please start a new tab and try again"
             PA_UserState.query.delete()
             db.session.commit()