* Added transpile() function to convert circuits between different quantum libraries
* Added various standard gates:
* A (2-qubit, 2-parameter gate that is locally equivalent to Can(1/2, t, t))
* CS (Controlled-S gate)
* CT (Controlled-T gate)
* CISwap (Controlled-iSwap)
* Margolus (A 3-qubit "simplified" Toffoli gate)
* Added various multi-qubit gates
* DiagonalGate
* ControlGate
* MultiplexedGate
* ConditionalGate
* MultiplexedRzGate
* MultiplexedRyGate
* Added (beginnings of) a tutorial
* Added tutorial/qf-tutorial-translate.ipynb
* Added tutorial/qf-tutorial-transpile.ipynb
* Added various collections of gates and operations
* OPERATIONS
* GATES
* STDGATES
* SIMULATORS
* CIRQ_GATES
* LATEX_OPERATIONS
* TERMINAL_GATES
* QSIM_GATES
* QUIL_GATES
* QISKIT_GATES
* QUIRK_GATES
* Added quantum Shannon decomposition
* Added QuTip interface
* Interfaces to external libraries are now imported at top level
(e.g. `import quantumflow as qf; sim = qf.BraketSimulator`)
* Miscellaneous improvements and bug fixes