1.1.15 release.
SecurityManager adjustments
Updated changelog, upgrade, added option to disable keys validation, added back automatic key generation
Fixed accidental removal
Removed missing key test
Fixes #3623: Added 'itemscope' to list of special attributes in renderAttribute
Fixes #2025: Upgraded jQuery to 1.11.1

- .addBack( selector ) replaces .andSelf()
- jQuery.browser() removed
Update UPGRADE
Update UPGRADE

typo
Fixes #3636: Upgraded jQuery UI to 1.11.2
Merge branch '1.1.16-branch'

Conflicts:
	CHANGELOG
	UPGRADE
	framework/YiiBase.php
	framework/yiilite.php
Update dutch translations.
Merge pull request #3664 from marcovtwout/i3663-update-dutch-translations

[skip ci] Update dutch translations
Changed variables usage in CSecurityManager messages to placeholders
Fixed placeholder names
check if YiiBase already exists

to avoid problems in certain composer setups

fixes #3539