Allow lambdas to accept arguments.

Syntax is taken from handlebars.js

Added 4.2.0 ref in CHANGELOG

..simply forgot that when preparing the v4.2.0 release

🚢 bump to version 4.1.0

🚢 bump to version 4.0.1

🚢 bump to version 4.0.0

🚢 bump to version 3.2.1

🚢 bump to version 3.2.0

🚢 bump to version 3.1.0

🚢 bump to version 3.0.3

🚢 bump to version 3.0.2