Add support for 2D arrays in InfoArrayValidator

[jonmmease]

Supersedes #1233, which didn't recover from the GitHub outage:

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Rework InfoArrayValidator to fix #1220

[saebaxp]

This line in InfoArrayValidator.validate_coerce() doesn't look like right:
is_v_2d = v and is_array(v[0])
for methods like 'animate' expecting their 'args' containing a first argument as a list of frame names (but it's not a really 2d array as a whole, I believe), above code gives an unexpected error.

Changing it to:
is_v_2d = v and all([is_array(vv) for vv in v])
corrected the issue.

Could you please give a look?

[jonmmease]

That's a good point @saebaxp, I've opened #1265 to track this

[saebaxp]

Thanks for the quick turnaround! @jonmmease