Add Date Restrictions/Qualifiers

[#1]

Description -

Currently while we are configuring fields for date type, it doesnt let us add any kind of validation on it. It would be great if there is a data validation option, eg - you can only enter dates in the future, or dates within a range. 

Why is this feature important to you -The use case for this is we want to restrict client users to select a date in the past where we are asking when do they want this work to be completed.

How would you like the feature to work - Either a Global Setting or a Project based setting preventing certain data selections. 

Current Behaviour - Users can include any date they want, even dates in the past on current projects. 

[#2]

I think this falls under field validation, at least when it comes to custom fields. These validation rules should be set per field.

If you're talking about any given date field (like a planned completion date) then I believe it should be set via project settings, task settings, ect. depending on the object. The settings could have a dropdown with some canned rules (future dates only, past dates only, weekdays only, etc.) along with a custom choice where you can type in field validation code (javascript, textmode or whatever syntax is decided upon).