Reorganize How to guides

[stevepiercy]

This is just a placeholder for now.

The How to guides have increased in number and the quantity of their content within each file has come to the point where it would benefit from a reorganization.

I'd like to see subsections within the How to guides, such as Troubleshoot, and Usage containing several groups of examples.

I'd also like to see a new Tutorial section. See Diátaxis for an explanation of the difference between Tutorial and How tos.

• Address Issue 987 - refactor icalendar.prop #1136 (comment) referencing https://icalendar.readthedocs.io/en/latest/how-to/usage.html#complete-recurring-meeting.