Merge the simpacks into the repo

[kousu]

I didn't realize I'd lost them, but they're submodules, not folders, so they just vanished when I moved their folders to modex/src/models/ and repulled.

Tutorials at:

• http://refactr.com/blog/2012/03/git-merging-two-repositories/
• http://jasonkarns.com/blog/merge-two-git-repositories-into-one/

At the same time, merge tcstewar/farm-eutopia in to to src/models.

[kousu]

This is what @vchynarov meant by #26