fix environments not working from cli
fix default environment value
Change posix module to optional dependency

- Add posix to optionalDependencies in package.json
- Change config.coffee to allow posix to be optional
- Change index.coffee to allow posix to be optional

Fixes #556
Fix invalid windows regex
Merge pull request #563 from jenius/sjs/fix-posix

posix and regex fixes for win32
environment tests
Merge pull request #564 from jenius/fix-environments

Fix environments
3.0.0-rc.10
uncomment env test assertions
Merge pull request #565 from joshrowley/uncomment-env-tests

uncomment environment test assertions
fix error code on compile fail, closes #560
tracking for cli commands
update deps: chokidar, colors