Fixed missing methods in mock stage

from openflexure_microscope.stage.base import BaseStage

from openflexure_microscope.utilities import axes_to_array

from collections.abc import Iterable

import numpy as np

class MockStage(BaseStage):

    def __init__(self, port=None, **kwargs):

        }

        return state

    def apply_config(self, config: dict):

        """Update settings from a config dictionary"""

        # Set backlash. Expects a dictionary with axis labels

        if 'backlash' in config:

            # Construct backlash array

            backlash = axes_to_array(config['backlash'], ['x', 'y', 'z'], [0, 0, 0])

            self.backlash = backlash

    def read_config(self) -> dict:

        """Return the current settings as a dictionary"""

        blsh = self.backlash.tolist()

        config = {

                'backlash': {

                    'x': blsh[0],

                    'y': blsh[1],

                    'z': blsh[2],

                }

            }

        return config

    @property

    def n_axes(self):

        return self._n_axis

    @property

    def backlash(self):

        return self._backlash if self._backlash else [0]*self.n_axes

        if self._backlash is not None:

            return self._backlash

        else:

            return np.array([0] * self.n_axes)

    @backlash.setter

    def backlash(self, blsh):

        if blsh is None:

            self._backlash = None

        elif isinstance(blsh, Iterable):

            assert len(blsh) == self.n_axes

        self._backlash = [int(blsh)]*self.n_axes

            self._backlash = np.array(blsh)

        else:

            self._backlash = np.array([int(blsh)]*self.n_axes, dtype=np.int)

    def move_rel(self, displacement, axis=None, backlash=True):

        pass