[WIP] Grid problem prerequisites for Clifford+T decompositions

[obliviateandsurrender]

Context:
This introduces and provides some grid problem based prerequisites necessary for number-theoretic Clifford-T decomposition methods.

Description of the Change:

1. [TODO] Grid representation.
2. [TODO] Grid Operators.
3. [TODO] 1-D Grid problem solver.
4. [TODO] 2-D Grid problem solver.

Benefits:

Possible Drawbacks:

Related GitHub Issues:

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