Add interpreter for BitcastConvertOp

[ghpvnist]

Here are the following constraints:

(I1) operand is a tensor.
(C1) Let `E` and `E'` be the `operand` and `result` element type,
respectively and `R = rank(operand)`:
* If `num_bits(E')` = `num_bits(E)`, shape(`result`) = shape(`operand`).
* If `num_bits(E')` < `num_bits(E)`:
  * `rank(result) = R+1`.
  * dim(`result`, `i`) = dim(`operand`, `i`) for all `i` in [0, `R`-1].
  * `dim(result, R) = num_bits(E)/num_bits(E')`.
* If `num_bits(E')` > `num_bits(E)`:
  * `rank(result) = R-1`.
  * dim(`result`, `i`) = dim(`operand`, `i`) for all `i` in [0, `R`-1).
  * `dim(operand, R-1) = num_bits(E')/num_bits(E)`.
(C2) Conversion between complex and non-complex types is not permitted.

These constraints will be comprehensively covered by the following tests:

I1: a) operand is not a tensor. (Covered by ODS).
C1: a) If `num_bits(E')` = `num_bits(E)`, shape(`result`) != shape(`operand`).
C1: b) If `num_bits(E')` < `num_bits(E)`: `rank(result) != R+1`.
C1: c) If `num_bits(E')` < `num_bits(E)`: dim(`result`, `i`) != dim(`operand`, `i`) for any `i` in [0, `R`-1].
C1: d) If `num_bits(E')` < `num_bits(E)`: `dim(result, R) != num_bits(E)/num_bits(E')`.
C1: e) If `num_bits(E')` > `num_bits(E)`: `rank(result) != R-1`.
C1: f) If `num_bits(E')` > `num_bits(E)`: dim(`result`, `i`) != dim(`operand`, `i`) for all `i` in [0, `R`-1).
C1: g) If `num_bits(E')` > `num_bits(E)`: `dim(operand, R-1) != num_bits(E')/num_bits(E)`.
(C2) Conversion between complex and non-complex types is permitted.

If we drop the "Covered by ODS" pieces, this will leave us with the following test cases:

C1a: If `num_bits(E')` = `num_bits(E)`:
     shape(`result`) != shape(`operand`).
C1b: If `num_bits(E')` < `num_bits(E)`:
     `rank(result) != R+1`.
C1c: If `num_bits(E')` < `num_bits(E)`:
     dim(`result`, `i`) != dim(`operand`, `i`) for any `i` in [0, `R`-1].
C1d: If `num_bits(E')` < `num_bits(E)`:
     `dim(result, R) != num_bits(E)/num_bits(E')`.
C1e: If `num_bits(E')` > `num_bits(E)`:
     `rank(result) != R-1`.
C1f: If `num_bits(E')` > `num_bits(E)`:
     dim(`result`, `i`) != dim(`operand`, `i`) for all `i` in [0, `R`-1).
C1g: If `num_bits(E')` > `num_bits(E)`:
     `dim(operand, R-1) != num_bits(E')/num_bits(E)`.
C2: Conversion between complex and non-complex types is permitted.

Notes:

• The interpreter assumes little endian representation, and we have Explore adding support for big endian architectures #1460 to address adding support for big endian architectures.

closes #1098

[sdasgup3]

I will add more comments in a while

[sdasgup3]

I will add more comments in a while

[sdasgup3]

This concludes my review for this PR.

[sdasgup3]

Reviewed the PR except for

1.  bitcastConvertManyToOne, bitcastConvertOneToMany and bitcastConvertOneToOne from this PR as there is a alternative proposal provided here.

[sdasgup3]

I approve the changes with a comment about the test case selection.