Add game server/password event information

Additionally, some unit tests were added and code was cleaned up.

Improvements focusing on website metadata

Write website metadata

We now write event metadata for that allows friendlylinuxplayers.org to
server event pages. These pages are now used in the iCalendar feed. The
calendar feed is updated when events are modified now.

Besides all of these files being written, events can now be marked as
not requiring game ownership to attend, and upcoming events are listed
by date.

Improve info messages and notifications

We now notify 24 hours before if an event takes place in more than 30
hours, 1 hour before if it takes place in more than 2 hours, at the mid
point if it takes place in at most 2 hours and more than 19 minutes, and
not at all if the event takes place in 19 minutes or less.

Improve the information messages

Add information subcommand

Fix calendar hyperlink

We now have a working iCalendar feed

Additionally, there have been improvements to startup time and
refactoring of some code.

We've reached a minimally-viable state!

flip-matrix-bot is now available for use in #flip:flip.earth (as
@bot:flip.earth). Try !f to interact with it.
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