Forced workdays

[pustserg]

Sometimes because of the holidays (at least in Russia), working days for the weekend can be moved back.
For example, because of the holiday on May 1, Saturday April 29 was a working day despite the fact that the 5-day working week was in the config.
date.workday? method returned false for this date. I want to be able to specify "forced_workdays" for such cases.
It works like a holidays option

workday = Date.parse("2018-4-29")
BusinessTime::Config.forced_workdays << workday

or for YAML config

business_time:
  forced_workdays:
    - April, 28, 2018