unset(conf, sid, opt) {
		return this.set(conf, sid, opt, null);
	}
Remove the given option within the specified section of the given
configuration.

This function is a convenience wrapper around
`uci.set(config, section, option, null)`.

@param {string} conf
The name of the configuration to remove the option from.

@param {string} sid
The name or ID of the section to remove the option from.

@param {string} opt
The name of the option to remove.