Consider supporting array configuration in validations

[DannyBen]

As discussed in #651

[meleu]

Hey @DannyBen

Real Life got in my way, 3 weeks passed and I still wasn't able to finish this...

I started taking a look at it today but then some questions paralyzed me.

Should we support both string and array? (just like we do for alias and examples.) The reason is that making it "array only" would be a breaking change, no?

Or maybe provide a brand new feature called validations (plural) supporting an array?

Are we going to provide both validate and validations? Or deprecate validate in favor of validations (for consistency sake)?

Does this feature really belongs to 1.3.2 or should we make it in 2.0.0?

What are your thoughts on this?

Can you pick this (so I can put my focus back in the tutorial)?

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By the way, can you release 1.3.2 with the #660 naming fix?

I understand this is a minor thing, in a comment that will be deleted by the user. But it's just so I can post the part 1 of the tutorial with an accurate information.

[DannyBen]

All good questions.

Can you pick this (so I can put my focus back in the tutorial)?

Sure. I will take it. Any change we do here will not be a breaking change.
I will update once I make some progress.

can you release 1.3.2 with the #660 naming fix?

Sure.

[DannyBen]

Implementation was larger than anticipated.
If it works as is, or with minor changes - great. But In case it will require additional work which will complicate it further, I might be inclined to revert it, as it is at the limit of the complexity-benefit ratio that I am willing to accept.

[DannyBen]

Released in 1.3.3.