Void/absorber as a component

[emil14]

Let compiler adds usage of void operator for all unused outports. Get rid of void as a special _effect.

void<t> (v t)

Note that void must not have any outports (just like root node).

Problem

The problem is in the typings. It's impossible with the header above to read from several outports if they have different types (which is usually the case)

Solution 1 - Any type

It's possible with

void (v any)

Related to #143

Solution 2 - Many voids

Create as many voids as we have unread ports, each with special <t>