option(cbiClass, ...args) {
		if (!CBIAbstractValue.isSubclass(cbiClass))
			throw L.error('TypeError', 'Class must be a descendant of CBIAbstractValue');

		const obj = cbiClass.instantiate([ this.map, this, ...args ]);
		this.append(obj);
		return obj;
	}
Add a configuration option widget to the section.

Note that [taboption()]{@link LuCI.form.AbstractSection#taboption}
should be used instead if this form section element uses tabs.

@param {LuCI.form.AbstractValue} optionclass
The option class to use for rendering the configuration option. Note
that this value must be the class itself, not a class instance obtained
from calling `new`. It must also be a class derived from
[LuCI.form.AbstractSection]{@link LuCI.form.AbstractSection}.

@param {...*} classargs
Additional arguments which are passed as-is to the constructor of the
given option class. Refer to the class specific constructor
documentation for details.

@throws {TypeError}
Throws a `TypeError` exception in case the passed class value is not a
descendant of `AbstractValue`.

@returns {LuCI.form.AbstractValue}
Returns the instantiated option class instance.