[Needs Review] Issue command bug fixes

[rudehn]

The ability to send commands to chaosbot via issue comments is now available. However there were a few major bugs with the first version.

This PR..

• [x] Runs commands from oldest to newest
• [x] Has slightly more error handling
• [x] Better validation of commands. /vote for :beers: will no longer be run.
• [x] Stop overwriting command comment. Bot would overwrite comment with command saying "Command has been run". This now updates on the bot status reply instead.
• [x] Don't show negative time remaining

[PlasmaPower]

I'll approve after lints are fixed.

[phil-r]

/vote for :beers: will no longer be run.

😭

[mark-i-m]

Nice job at @rudehn :beers: Much needed improvements!

[mark-i-m]

@PlasmaPower Meritocracy?

[mark-i-m]

@rudehn The title of this PR is inaccurate. This is unacceptable. Remove [Needs Review] this instant!!! :rage:

[chaosbot]

:ok_woman: PR passed with a vote of 9 for and 0 against, a weighted total of 9.0 and a threshold of 6.5, and a current meritocracy review.

See merge-commit ff748cbdefc1c93516a44c48fe5a0223b78939a5 for more details.

[phil-r]

🎉 That did work!