Feature request: change logging level on demand via chatops

[pmonks]

Description of Problem:

When an unexpected issue occurs with the production instance of the bot, I want to be able to change the logging level dynamically, by sending the bot a direct message, so I can triage the issue without having to redeploy the bot.

When I have triaged the issue, I want to "reset" the logging level to its configured defaults (also by sending the bot a direct message), so that the bot returns to its pre-triage logging state.

Potential Solutions:

Implement two new "secret" commands:

1. "!setlogging loglevel [logger]"
2. "!resetlogging"

See this code for how to modify logging levels.