load extensions before preloading components to have aliases set for
extensions like debug module.

ActiveRecord Interface and BaseAR

fix doc typo

* master: (30 commits)
  replaced inheritdoc tags.
  doc cleanup.
  Moved key serialization from data provider to data viewers.
  Fixes #1356: Alias for authFile in rbac/PhpManager not resolved
  Fixes #1296: stricter check of dashes in route.
  Fixes #1362: added itemOptions to Html::radioList and checkboxList.
  Fixes #1362: doc fix.
  really small doc typo fix
  Fixes #1332: generate subdirectories when needed during message extraction process.
  typo fix.
  Fixes #1335: support view extension fallback
  More TDB for the guide
  Added reference to Composer section of the guide from 1.1.x differences page
  Better docs structure and minor fixes
  More docs on performance
  Structure for console application docs
  Docs on using behaviors
  doc fix.
  Refactored MessageInterface::send().
  refactored EmailTarget with the new mailer interfaces.
  ...