quoteIdentifier() & quoteIdentifierChain() bug

Identifier escaping is done means of doubling the delimiter character, and not using a backslash.
quoteIdentifierInFragment() also has wrong escaping
Added tests for ensuring escaping
Add empty option before empty check
Removed check for empty option
Updated test for PR#2837
Resolve naming conflicts in foreach statements
OutputCache: fixed storing of catched output
Fix : change self:: with static::
in Zend\Debug\Debug.php in calling static propery/method
remove unused const in Zend\Barcode\Barcode.php and fix self:: to static::
Fix : change self:: with static::
in Zend\I18n\Translator\Plural\Rule.php in calling static propery/method
Fix : change self:: with static:: in Zend\Text\Table in calling static propery/method
change self:: with static:: in Zend\XmlRpc\AbstractValue in calling static property/method
fix accident XMLRPC_TYPE_ARRAY changed to static
minor: updated injectViewModel's docblock

* removed a double space.
* removed a comma.
reduce code by assign directly
remove unused 'use Zend\Stdlib\RequestInterface' in Zend\Mvc\Application
fix docblock namespace
fixed proxy keys being incorrectly set due to normalising in Zend\Http\Client
Removed test for PR#2837