SDVariable Improvements

[rnett]

What changes were proposed in this pull request?

Fixing:

• Non-SDVariable invertPermutation #7364
• Have SDVariable use Kotlin operator method names #7367
• Add reshape, permute and other common SameDiff operations to SDVariable #7368

How was this patch tested?

• Unit tests for invertPermutation

Should I add unit tests for the SDVar methods? They all call already implemented methods.

[rnett]

I can add a permute(long...) that just casts to int, is that useful enough to be worth it? I always end up using ints.

[AlexDBlack]

LGTM 👍

Should I add unit tests for the SDVar methods? They all call already implemented methods.

Because they call existing methods (which are well tested), I think we can safely skip tests for these.

I can add a permute(long...) that just casts to int, is that useful enough to be worth it? I always end up using ints.

No, we don't need that that. INDArray only has integer permute. As a general rule, we use longs for shapes/lengths, ints for dimensions/axis.