Update DefaultValueValidator.php

Allow the default value to be a closure
Update CHANGELOG.md
Better naming for Schema properties
IntegrityException should be thrown for relational DBs only
Added CUBRID support for throwing integrity exception
Fixed PostgreSQL test
Renamed handleError to handleException
Fixes #699: fixed wrong usage of self and static
Update DefaultValueValidator.php
adjusted elasticsearch extension to version 1.0 of ES

breaking changes.
Merge branch 'master' of github.com:yiisoft/yii2

* 'master' of github.com:yiisoft/yii2:
  Fixes #699: fixed wrong usage of self and static
  Fixed wrong links
Removed duplicate property
Fixed rbac tests to use migration
RBAC migration is now aware of custom table names, speeded up RBAC tests
Fixed RBAC migration for SQLite
Simplified RBAC DB manager test
Fixed mongodb to use non-deprecated method of determining if there's an active connection
Re-init application if it was destroyed during RBAC test
Fixes #3383: Added `$type` parameter to `IdentityInterface::findIdentityByAccessToken()`
correct typo in phpdoc for HttpBearerAuth class