Added mkdocs

[shimwell]

Also needs a random function to show docstrings for

import typing

def csg_to_cad(
    csg_filename: str,
    csg_format: str,
    output_filename: str,
    bounding_box: typing.Tuple(float),
) -> str:
    """Converts a CSG geometry into a CAD geometry and saves a STEP file

    Args:
        csg_filename (str): the filename of the CSG file
        csg_format (str): the format / Monte Carlo code of the CSG file.
            Acceptable options are 'openmc', 'mcnp', 'serpent'
        bounding_box (typing.Tuple): A bounding box for the geometry in the
            format lower left x,y,z and upper right x,y,z
        output_filename (str): the filename of the produced CAD file

    Returns:
        str: output file path of the CAD file produced
    """
    return 'hello world'

def cad_to_csg(
    cad_filename: str,
    csg_format: str,
    output_filename: str,
    start_cell_id: int,
) -> str:
    """Converts a CAD geometry into a CSG geometry in the specified format

    Args:
        cad_filename (str): the filename of the CAD file
        csg_format (str): the format / Monte Carlo code of the CSG file.
            Acceptable options are 'openmc', 'mcnp', 'serpent'
        output_filename (str): the filename of the produced CSG file
        start_cell_id (typing.Tuple): A bounding box for the geometry in the
            format lower left x,y,z and upper right x,y,z

    Returns:
        str: output file path of the CSG file produced
    """
    return 'hello world'

[shimwell]

ah sorry I made a few mistakes in this PR, I mean to make the PR on my own fork and finish it before making it here. Really sorry I shall fix it asap