Broke out tasks into dep and history.
Added dep task as a test subtask
Merge branch 'deps' of https://github.com/davglass/yeti into dep-task

Conflicts:
	scripts/postinstall.js
Include externally maintained libraries.
Re-add missing DOH download. Introduce dep/dev.

 - Do not include dev-only JS libs in the npm package.
 - Add missing DOH file downloads after Dav's merge.
 - Move test fixture references to use dep/dev directories.
Add npm dependencies' license information.
Remove dep target from test target.

Script dependencies should be installed with the install target
before tests run.

Add `./jake dep` to Makefile's install target to make sure
these script dependencies are installed if make is used.
Add `./jake dep` as pretest script.

Dependencies need to be installed before `npm test yeti` can run.
Revise .npmignore to exclude dev-only files.
Merge branch 'dep-task'. Fix #126.