fix #33: turn segment utils into filters
Implementation is here, only problem: it hasn't been tested in any way.
Basic tests for cut components now pass
fix #40: update the tests of Formula to use argsFn
fix #36: subcomponent args can now be used, + new subcomponent syntax
Merge branch 'master' of github.com:byte-foundry/prototypo
component.firstSegment and component.lastSegment should be inverted in an inverted component