Merge remote-tracking branch 'origin/1.6' into 1.7

doc/sphinx/book/administration.rst

doc/sphinx/book/app/a-errcodes.rst

doc/sphinx/book/app/c-lua_tutorial.rst

doc/sphinx/book/app/d-plugins.rst

doc/sphinx/book/box/authentication.rst

doc/sphinx/book/box/box_introspection.rst

doc/sphinx/book/box/box_schema.rst

doc/sphinx/book/box/box_space.rst

doc/sphinx/book/box/index.rst

doc/sphinx/book/box/limitations.rst

doc/sphinx/book/box/sophia_diff.rst

doc/sphinx/book/box/triggers.rst

doc/sphinx/book/configuration/cfg-replication.rst

doc/sphinx/book/configuration/index.rst

doc/sphinx/book/connectors/__c.rst

doc/sphinx/book/connectors/__php.rst

doc/sphinx/book/connectors/__results.rst

doc/sphinx/book/replication/index.rst

doc/sphinx/book/user_guide_getting_started.rst

doc/sphinx/reference/box_once.rst