Copy schema 1.0.0 userguide from 1.0.0-rc6 branch.

Copied the _posts/userguides/schema/ directory from the 1.0.0-rc6
branch (@SHA1 de18956310076a  DOCS-60) for the KijiSchema 1.0.0
release.
Update links to API docs, userguides for Schema 1.0.0.
Fix links to api-docs.kiji.org.

_config.yml was pointing to the old docs.kiji.org/apidocs/ URLs.
Update HTML formatting in "Managing Data" (schema 1.0.0 UG).