v0.3.6

Added

• TAT.hpp: Add clear_fermi_symmetry for tensor with fermionic symmetry, which convert the tensor to the simplest
  fermionic tensor, tensor with parity symmetry.
• TAT.py: Add python binding for clear_fermi_symmetry.
• tetragono: Check whether the state is None when dump the state to file to avoid overwriting file by mistake.
• tetragono: Add gm_clear_symmetry for sampling lattice.
• tetragono: Add gm_run_g and ap_run_g for middle level API. These are generators, which yield the energy of the
  state before gradient descent after every gradient step.
• TAT.hpp: Cut is used directly for the dimension cut in svd. Cut will detect the type of the input to determine
  whether it is relative cut or remain cut, if nothing provided, the behavior of previous NoCut will be used. And user
  could also set remain cut and relative cut together.

Changed

• tetragono: new_dimension in simple update will be intepreted as the threshold of singular value when it is float.
• TAT.hpp, TAT.py: clear_symmetry will return NoSymmetry tensor or ParityTensor based on whether the original tensor
  is fermionic. The previous behavior would give NoSymmetry tensor only, which is dangerous for fermionic tensor, is
  renamed to clear_bose_symmetry.

Deprecated

• TAT.hpp: NoCut, RemainCut, RelativeCut is deprecated, please use Cut directly.

Fixed

• tetragono: Fix a bug in merging physical edges during simple update. When the hamiltonian on single site with a
  large dimension is operated, the dead loop would occur previously.