Add http:// before httpbin.org; fixes #489
Update link targets; fixes #447
Merge branch 'issue-447-mongodb-links'
Remove 'protobuf' reference; fixes #474
Merge branch 'issue-474-protobuf-refs'
Link to binary-storing article from r.binary api
Move query language docs under language folders.
Add language tags to query language docs.
Add python and ruby nested-fields docs.
Merge pull request #492 from grandquista/grandquista/nested_fields_brackets

Create python and ruby nested fields documents for #491.
Revert "Create python and ruby nested fields documents for #491."
Merge pull request #493 from rethinkdb/revert-492-grandquista/nested_fields_brackets

Revert "Create python and ruby nested fields documents for #491."
Add python and ruby nested-fields docs.
Add @grandquista's nested-field docs; fixes #491
Fix lambdas; fixes #486
Add index file to publish-subscribe