Blueqat

New Features
- Add JSON serializer/deserializer. Refer [here](https://blueqat.readthedocs.io/en/latest/json.html).

Destructive Changes
- `Operation.create` method is added. All subclasses of `Operation` class must implement it.
- Remove circuit-local default backend, move `blueqat.circuit.GATE_SET` to `blueqat.gateset.GATE_SET`.
- Use `GATE_SET` directly is not recommended. Please use `blueqat.gateset.create` or `blueqat.gateset.get_op_type`.
- u1/u2/u3, cu1/cu2/cu3 gates are completely deleted.

Advanced Notice
`blueqat.wq` module will be deleted.

New features
- Add the following methods. These methods are equivalent with `Circuit.run()` with `returns="..."` arguments, but these are typed.
- `Circuit.statevector() -> np.ndarray`
- `Circuit.shots(n: int) -> Counter`
- `Circuit.oneshot() -> Tuple[np.ndarray, str]`

Release Date
10, Jun. 2021

Debug
- Repair 1 qubit gate decomposition function
- Correct gamma factor of `U.matrix()`

Release Date
May. 21, 2021

Enhancement
- Add `ryrz_decomposer`

Debug
- Debug wq (Ising model) module
- Debug phase/cphase gate matrix

How To Install
Update:
Jupyter Notebook: `!pip install -U blueqat`
Shell: `pip install -U blueqat`

Install:
Jupyter Notebook: `!pip install blueqat`
Shell: `pip install blueqat`

Release Date
Mar. 26, 2021

Changes
**U1/U2/U3/CU1/CU2/CU3 gates are deprecated and no longer working.**

- U1(θ) → RZ(θ)
- U2(φ, λ) → U(π/2, φ, λ, -0.5 * (φ+λ))
- U3(θ, φ, λ) → U(θ, φ, λ, -0.5 * (φ+λ))
- CU1(θ) → CR(θ)
- CU2(φ, λ) → CU(π/2, φ, λ, -0.5 * (φ+λ))
- CU3(θ, φ, λ) → CU(θ, φ, λ, -0.5 * (φ+λ))

are alternative.

Enhancement
Add U/CU gate and SX/SXDG gate.

Release Date
Mar. 10, 2021

Enhancement
- Input initial statevector for numpy and numba backend. 101
py
vec = Circuit(2).x[0].run()
count = Circuit().x[1].m[:].run(initial=vec, shots=100)
=> count is {"11": 100}


Changed
- Cache is not stored after running. If caching is required, use `circuit.run(save_cache=True)`.

Debug
- Correct qgate backend, SWAP gate error.