improve main layout to use % viewport sizes and prefer courier typefaces
add "inventory" as verb, not just "inv"
pass owner name to inventory constructor for more meaningful logging
add tests for making "sweet coffee" - both at the artefact-only level and at the player action level
add sugar and sweet coffee to the game map contents
add artefact support for combining 2 objects and delivering a result. Note, "combine" does not destroy the originals, the caller must handle that at the moment
ensure we can add things to a container in a location if needed.
write first version of player "combine" function - called from "put". This has some really ugly hacks around weight in it in order to check whether containers can carry items when they already contain one of the ingredients. This is some of the ugliest code in the game so far!