Add support for specifying simple options as CLI arguments

[thewelshrich]

@sertalpbilal as discussed briefly on Discord, this is what I use to be able to quickly modify settings on the fly - for the sake of simplicity it only supports numeric and string options;

• 'horizon'
• 'ft_value'
• 'itb_value'
• 'no_transfer_last_gws'
• 'xmin_lb'
• 'secs'
• 'gap'
• 'num_transfers'
• 'hit_limit'
• 'use_wc'
• 'use_bb'
• 'use_fh'
• 'future_transfer_limit'
• 'cbc_path'
• 'iteration'
• 'iteration_criteria'

Please suggest any changes or feel free to decline the PR entirely if you don't want it included! :)

[sertalpbilal]

Thanks @thewelshrich!