Move sample_completion to script/.
Modify script/completion to run from its new home.
Adding back Code of Conduct URL field.
Merge pull request #463 from ycombinator/code-of-conduct

Adding back Code of Conduct URL field
Adding sign-up button to header

- Fixes #464
Merge pull request #467 from rackerlabs/gh-464

Adding sign-up button to header
Adding code samples for node.js databases
Merge pull request #468 from rackerlabs/cloud-db-nodejs

Adding code samples for node.js databases
Merge pull request #414 from rackerlabs/script-completeness

script/completeness
Merge branch 'dev'