Highlight dates, fiscal years/quarters and add tooltips that show the date in the user's local date format
Created by: felixfbecker
If you keep forgetting when different fiscal quarters start (like me), or if you're confused by the YYYY-MM-DD date format we use, or just would like to be able to know what day of the week a date referenced in the handbook is, this PR is for you.
It highlights all references to fiscal years, quarters, and dates/times with a dotted underline, and when hovered, will show the date (or start of the quarter) in the user's local date format complete with day of the week, timezone, etc.
