Walter/mongo db ci

[waltervan00]

Closes #64
Endpoint changes:
DELETE /api/card now issues 410 when attempting to delete someone else's card id.

Ci changes:
Script included to spool up instance of server and mongodb on ci environment for calling api tests to self.

To Run locally: the following shell script is provided, runnable in Ubuntu
Integration tests automatically default to the values shown here (hard coded in tests but first accept environmental values, if any). You'll need to start a mongodb instance at port 27017 (or what's configured to DB_TESTING_PATH) and establish a server using the save database path used for the mongodb, with port 8080.

export DB_TESTING_PATH="mongodb://localhost:27017/integrationTests"
export SERVER_PORT="8080"
hash=$(node -p "crypto.randomBytes(32).toString('base64')")
npm start -- -s $hash -c $DB_TESTING_PATH -p $SERVER_PORT

[chomosuke]

Would be nice if we can run all tests with 1 command.

But, this project is coming to an end, so that does not really matter.