Re-implementing UnaryExpression to make it more simple
Allowing isNull and isNotNull to accept ExpressionInterface
Remove broken database related features for i18n shell.

The i18n shell has not had any database related features for quite
a while. Remove them until we can sort out how to provide the ability to
seed the i18n tables again.

Refs #3835
Automatically quoting strings passed to isNull and isNotNull

All other methods in QueryExpression had the same behavior so it
made sense to support that here too. Fixes #3836
Merge pull request #3841 from cakephp/issue-3835

Remove broken database related features for i18n shell.
Fix 'either' typo in Time
Fix 'IntlDateFormatter' typos in Time
Fix docblock errors.
Fix url option key.

Closes #3845
Merge pull request #3846 from ADmad/bugfix-3845

Fix url option key.
Merge pull request #3844 from cakephp/3.0-fix-notnull

3.0 fix notnull missing identifier quoting
Remove BC mapping of "ext" to "_ext".
Rename option "ssl" to "_ssl" for consitency with other options.
Allow to use closure in QueryExpression

Allow to use closure in QueryExpression. Fixes #3852
Added test case for closures in QueryExpression.
Fixed comment
Merge branch '2.6' into 3.0

Conflicts:
	app/Config/Schema/db_acl.php
	app/Config/Schema/db_acl.sql
	app/Console/cake.php
	lib/Cake/Console/Command/UpgradeShell.php
	lib/Cake/Console/ShellDispatcher.php
	lib/Cake/Console/Templates/skel/Console/cake.php
	lib/Cake/Core/App.php
	lib/Cake/Model/AclNode.php
	lib/Cake/Model/Datasource/Database/Mysql.php
	lib/Cake/Model/ModelValidator.php
	lib/Cake/Model/Validator/CakeValidationSet.php
	lib/Cake/Test/Case/Core/AppTest.php
	lib/Cake/TestSuite/Coverage/BaseCoverageReport.php
	lib/Cake/Utility/CakeTime.php
	lib/Cake/View/Helper/JqueryEngineHelper.php
	lib/Cake/View/Helper/MootoolsEngineHelper.php
	lib/Cake/View/Helper/PrototypeEngineHelper.php
	src/Cache/Engine/ApcEngine.php
	src/Configure/Engine/IniConfig.php
	src/Configure/Engine/PhpConfig.php
	src/Console/ConsoleOptionParser.php
	src/Network/Email/Email.php
	src/Network/Request.php
	src/View/View.php
	tests/TestCase/Network/RequestTest.php
	tests/TestCase/View/Helper/HtmlHelperTest.php
	tests/TestCase/View/ViewTest.php
Merge pull request #3855 from ADmad/3.0

Merge 2.6 into 3.0
Merge pull request #3838 from cakephp/revert-3646-no-truncate-fixture

Revert "No truncate when drop table."

Not truncating tables when they are created causes a number of 
issues in ControllerTestCases as indicated by the comments in #3646 post merge.
Merge pull request #3849 from ADmad/3.0-router

Remove backwards compatibility mapping for `ext` property.

Remove the ext -> _ext mapping and make the ssl option more consistent with 
other 'meta' options by renaming it to `_ssl`.
Update TupleComparisonTest.php