RethinkDB 1.7: hot backup, atomic set and get, 10x insert performance improvement

New release of RethinkDB: 1.7 "Nights of Cabiria".

This release includes the following features and improvements:

1. Tools for CSV and JSON import and export
2. Support for hot backup and restore
3. ReQL support for atomic set and get operations
4. A powerful new syntax for handling nested documents
5. Greater than 10x performance improvement on document inserts
6. Native binaries for CentOS / RHEL
7. A number of small ReQL improvements (explained below)

See the full list of over 30 bug fixes, features, and enhancements.