Method HipsSurveyProperties.tile_access_url returns incorrect results

[tboch]

Current method HipsSurveyProperties.tile_access_url is:

    @property
    def tile_access_url(self):
        """Tile access URL for a HiPS surveys"""
        return self.base_url + '/Norder' + str(self.hips_order) + '/Dir0/'

I see 2 problems with this:

• order is always the maximum order of the HiPS
• the directory number is hard-coded to Dir0 which will lead to wrong results once we try to access tiles with order>4

Thus, I'd suggest adding 2 arguments and adjust the code so that the method signature becomes:

    def tile_access_url(self, order: int, tile_index: int):
    ...

[tboch]

Fixed by @adl1995 in #52