adding objects to sprite inventories
adding a wall to demo object carrying
adding a demo box drop
moving inventory moving into sprite.cpp
mowing grass example
introducing challenge_helper, a static class of useful functionality for challenge writing
correcting makefile indentation
adding challenge_helper, forgotten from last commit
removing code, now in challenge_helper
Merge branch 'master' into font-rendering
storing status in sprite for later image intergration
Merge branch 'master' of github.com:heidi-ann/zygote
fixing click to switch focus
Fixes a bug where updating tiles doesn't work
Merge branch 'master' of https://github.com/heidi-ann/zygote
Fixes #76
Fixing layers renderable and sprites renderable
adding in focus icon to sprites
Merge branch 'master' of github.com:heidi-ann/zygote
using the new is_renderable option