Merge pull request #66 from eile/master

Tweak Makefile so 'make previously-unknown-target' works
Merge pull request #67 from eile/master

Clean up test target naming
Merge pull request #68 from eile/master

nasm is a required dependency for jpegturbo
Merge pull request #69 from eile/master

Force CMake run after update, update README
Merge branch 'master' of github.com:Eyescale/Buildyard
Update git externals