Create separate logger file and add log levels

https://github.com/cjaiello/Slack-Standup-Report-Bot/blob/master/logger.py

Like the file above, create a separate logger file that app.py references, and then add logging levels for types of events.

Read the linked logger.py example, then inspect app.py to identify how logging is currently handled. Create the separate logger integration and define event logging levels; done means app.py references the logger and distinguishes event types by level.

Written by the indexing model from the issue text.