User CP input validation - move to datahandler

[euantorano]

The user CP do_profile action has some validation done in usercp.php that then uses error(). This validation should be moved to the user data handler:

• [x] Away return date
• [ ] ICQ number
• [ ] Skype/Google hangouts details

[Ben-MyBB]

I'll take a look at creating a PR for this to go into 1.8.24.

[yuliu]

Hmm, just found out that these input fields also exist in ModCP but don't have validations. So #4014 isn't enough, and moving the validations to user handler should benefit both UserCP and ModCP, and probably AdminCP..

[effone]

Just a note to put here, I am willing to implement a date validation function affecting all date inputs in MyBB. Currently MyBB accepts impossible dates like 31-2-2020 (d-m-Y)

[Eldenroot]

@Ben-MyBB - are you willing to continue with this?

[Ben-MyBB]

@Eldenroot I probably don't have the time to continue this one for now so I've unassigned myself, feel free to complete if you wish.