Uninstall plugin packages.

    Plugin packages must have a directory with the same name as the package in
    the following directory:

        <conda prefix>/share/microdrop/plugins/available/

    Parameters
    ----------
    plugin_name : str or list
        Plugin package(s) to uninstall.
    *args
        Extra arguments to pass to Conda ``uninstall`` command.

    Returns
    -------
    dict
        Conda uninstallation log object (from JSON Conda uninstall output).

def uninstall(plugin_name, *args):
    '''
    Uninstall plugin packages.

    Plugin packages must have a directory with the same name as the package in
    the following directory:

        <conda prefix>/share/microdrop/plugins/available/

    Parameters
    ----------
    plugin_name : str or list
        Plugin package(s) to uninstall.
    *args
        Extra arguments to pass to Conda ``uninstall`` command.

    Returns
    -------
    dict
        Conda uninstallation log object (from JSON Conda uninstall output).
    '''
    if isinstance(plugin_name, types.StringTypes):
        plugin_name = [plugin_name]

    available_path = MICRODROP_CONDA_SHARE.joinpath('plugins', 'available')
    for name_i in plugin_name:
        plugin_module_i = name_i.split('.')[-1].replace('-', '_')
        plugin_path_i = available_path.joinpath(plugin_module_i)
        if not _islinklike(plugin_path_i) and not plugin_path_i.isdir():
            raise IOError('Plugin `{}` not found in `{}`'
                          .format(name_i, available_path))
        else:
            logging.debug('[uninstall] Found plugin `%s`', plugin_path_i)

    # Perform uninstall operation.
    conda_args = ['uninstall', '--json', '-y'] + list(args) + plugin_name
    uninstall_log_js = ch.conda_exec(*conda_args, verbose=False)
    # Remove broken links in `<conda prefix>/etc/microdrop/plugins/enabled/`,
    # since uninstall may have made one or more packages unavailable.
    _remove_broken_links()
    logger.debug('Uninstalled plugins: ```%s```', plugin_name)
    return json.loads(uninstall_log_js.split('\x00')[-1])