Allow user to choose algorithm in hafnian wrapper

[josh146]

Currently, when calling the hafnian Python wrapper, all you specify is whether recursive is True or False:

hafnian(A, loop=True, recursive=True, quad=True, approx=False, etc...)

We then apply logic to call the best case hafnian algorithm considering the matrix+options the user has provided.

We should modify it to look like this:

hafnian(A, loop=True, algorithm="best", options={})

where algorithm is a string containing the algorithm to use:

• best is the current logic (and the default)

• recursive

• trace

• approx

and options are the algorithm specific options, i.e. options={'samples': 100} for the approx algorithm, options={'quad': True} for the recursive, options={'powtrace': 'eigenvalues'} for the trace algorithm, etc.

Note: the moment/repeated hafnian will have to remain its own function, since it also takes rpt as an argument.

[sduquemesa]

@nquesada is this still relevant? Current function signature here