inconsistency in FBA flavour invocations

[lptolik]

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Is your feature related to a problem? Please describe it.

There are three flavours of FBA in cobra: FBA, pFBA, and geometric FBA. The plain FBA (model.optimise) has the argument raise_error to specify whether you want an exception to be raised. Neither pFBA nor geometric FBA has this argument. I think it would be nice if the invocation of all flavours of FBA would be consistent.

Describe the solution you would like.

Within all three functions pattern

m.slim_optimize(error_value=None)
solution = get_solution(m, reactions=reactions)

is used, but only in the plain FBA (model.optimise) raise_error is propagated into get_solution.