Simply flask app definition

[ABrain7710]

Description

• Simplify the definition of the flask app in the server.py file.
• The flask app is no longer defined in a class. It was defined as a class before so the engine could be passed to all the routes through the create_routes() function that had to be defined in each file that had routes. Also the routes were loaded onto the flask app by importing the create_routes() function from each routes file. This complexity was making it difficult for developers to add routes and understand how they are added to the flask app. To minimize this complexity I have changed the flask app to be defined at the module level rather than in a class. Also the routes are added to the flask app by importing the routes from all the different routes files. Then each routes file now imports the engine and flask app from the server.py file rather than defining a create_routes() function`.
• The flask app is also no longer preloaded. I did this so we don't have to worry as much about the database engine and when it is created.
• The metrics are still loaded the same way they were before, just all the functionality has been moved into the module rather than on the Server class
• Also the transform function was renamed to route_transform due to a conflict with another libraries function

Signed commits

• Yes, I signed my commits.