closes #522
Updated index to reflect new (short) 'engine' message (merged with solomon's new text), also moved around the layout a bit and fixed some small text errors.
Merge pull request #523 from steakknife/522-docker-build

* Builder: use any whitespaces instead of tabs
Implemented  command
missing comma
CouchDB example page was titled redis
README: fix Markdown formatting
Merge pull request #546 from shamrin/patch-3

- Documentation: fixed README formatting
Added doc page for new search command
Added actual doc file
Merge pull request #542 from dotcloud/docker-search

+ Registry: Add docker search top level command in order to search a repository
Merge pull request #535 from dhrp/website_update

* Documentation: updated www.docker.io website.
Merge pull request #544 from DanielVF/master

- Documentation: Fixed CouchDB example page header mistake