[WIP] Elasticsearch

far better than depending on fat guzzle

fixes #1319

* master:
  fixed broken sphinx AR::attributes() declaration
  updated properties of extensions
  fixed cubrid limit
  added redis Session
  allow redis connection to be configure directly in cache
  removed unneeded setting.
  refactored redis cache.

Conflicts:
	extensions/redis/README.md

Model::attributes() has been made static

as suggested in issue #1316

fixes #1316

* 'master' of github.com:yiisoft/yii2:
  removed unneeded setting.
  refactored redis cache.

[ci skip]

* master: (59 commits)
  updated ext composer.json for issue labels
  moved redis to extensions
  fixed whitespaces
  update composer to include sphinx
  Added initial steps about configuring DB-based RBAC
  Fixes #1297: CSRF not generated on error pages
  fixes #1158 mentioned @web alias in docs
  Merged RBAC draft into authorization
  "yii\sphinx\ActiveQuery" updated to throw exception on conflict between "asArray" and "snippetByModel" options.
  Code style and docs at "yii\sphinx\*" fixed.
  Docs for Sphinx extension updated.
  Redundant typecast removed from yii\sphinx\ActiveRecord::create()
  yii\sphinx\Command reworked to extend yii\db\Command. yii\sphinx\DataReader removed.
  Sphinx Active Record updated to be compatible with ActiveDataProvider.
  Sphinx documentation updated.
  Sphinx documentation updated.
  Sphinx has many relation test prepared.
  Sphinx Query refactored.
  Create relation methods added to Sphinx Active Record.
  Sphinx Query Builder updated to respect column types for where statements
  ...

[ci skip]

Sphinx fulltext search engine integration

* master:
  Fixes #1253
  Fixes #1310: ActiveRelation does not preserve order of items on find via() and viaTable()
  fixed limit/offset for sqlite,mysql and cubrid
  fixed test break.
  Fixed test break.
  Fixes #1301: fixed scenario generation when there are "except" scenarios.
  support for batch insert in sqlite older than 3.7.11
  Fixes #1298: supporting route with trailing slash.
  Fixes #1296: stricter check of dashes in route.
  Fixes #1307: move batchInsert() to base class.
  Update apps-advanced.md