Add support for fiscal year offset for relative date syntax

Our financial year does not follow the calendar year but runs from August-July.
it would help us create better filters if you implemented the following 2 things:

  1. Add an admin setting for the financial year start, where we can set the month our financial year starts. It should default to January as most companies’ financial years follow the calendar.
  2. Add a new relative date format setting, that supports the following things:
    fiscal year to date, this fiscal year, and the last fiscal year.

I can write august to today to get fiscal year to today.