Mirror circuit test suite and debugging

Upon suggestion from the Unitary Fund team, Qrack has been debugged against the newly developed [mirror] suite of "mirror circuit" (or "Loschmidt echo") integration tests, at all levels of the layer stack. For scope, about 20+ separate logical bugs were fixed. Random mirror circuits were generated to the exhaustion of detecable bugs, mostly at the 6 qubit width by 6-plus-inverse qubit depth level, but also ultimately for 27 qubits width by 6-plus-inverse depth.

In the process of refactoring and debugging, QStabilizerHybrid has also been extended with single-qubit matrix product state buffers that are commuted around control qubits, which are now effectively "trimmed" like with the Schmidt decomposition techniques of QUnit, to significantly increase the breadth of circuits which can be handled as Gottesman-Knill sub-states of QUnit.

Thank you to @paniash for contributing README documentation improvements and GitHub issue discussion, during the Unitary Fund's unitaryHACK!