Add solvers tolerant to infinite values

[philippkraft]

The nice error reporting for not finite results in connections can render recoverable errors to be unrecoverable. By allowing some retries in a solver, calculations can become more robust

Proposed solution

Change cmf.integrator.call(...) to the following:

    def __init__(self, project, err_tol=1e-9, max_errors=10):
        super().__init__(project, err_tol)
        self.errors = []
        self.max_errors = max_errors

    def __call__(self, t, reset=False):
        import sys
        until = self.t + t if t < self.t else t
        while self.t < until:
            try:
                self.integrate_until(until, reset=reset)
            except RuntimeError as e:
                if len(self.errors) < self.max_errors:
                    self.errors.append((self.t, e))
                    self.reset()
                    sys.stderr.write(str(e) + '\n')
                else:
                    raise

        return self.t

[philippkraft]

Availale via solver.run(..., max_errors=10)