another update to the readme

- shorten 'getting started' section, change to
  'installation'
- move everything except amd and cjs to
  docs/installation.md
- add simple usage example
- add link to license
- add contributing guide
- move running tests to contributing guide
update example to 'done' syntax
update readme with new examples
run-script > run
corrections in AMD installation
add curl.js amd example
Merge pull request #229 from jenius/readme

Update README. Add installation and contributing docs.