2.9.0

New features

• Added Pyramid events, triggered when the content of a resource has changed. (#488)
• Added cliquet.includes setting allowing loading of plugins once Cliquet
  is initialized (unlike pyramid.includes). (#504)

Protocol

• Remove the broken git revision commit field in the hello page. (#495).

Breaking changes

• Renamed internal backend classes for better consistency. Settings
  remain unchanged, but if you imported the backend classes in your
  Cliquet application, it will break (#491).
• cliquet.schema is now deprecated, and was moved to a cliquet.resource
  module. (#505)
• Resource collection attribute is now deprecated. Use model attribute instead. (#506)

Internal changes

• Rework PostgreSQL backends to use composition instead of inheritance for the
  client code. (#491)
• Replace DROP INDEX by a conditional creation in PostgreSQL schemas (#487, #496
  thanks @rodo)
• Documentation and minor refactors in viewset code (#490, #498, #502)
• Add the build-requirements, distclean and maintainer-clean Makefile rules.
• Documentation JSON patch format. (#484)
• Fix for permission among record fields in 412 errors. (#499)