Deprecate the P3P plugin and set it to disabled for new installations.
[Code Test]Implement tests for JLayout base
[x] JLayoutbase->setOptions() returns a JLayoutbase instance with empty parameter.
 [x] JLayoutbase->setOptions() returns a JLayoutbase instance with JRegistry parameter.
 [x] JLayoutbase->setOptions() returns a JLayoutbase instance with an array parameter.
 [x] JLayoutbase->getOptions() returns a JRegistry object when options parameter is empty.
 [x] JLayoutbase->getOptions() returns a JRegistry object when options parameter is an array.
 [x] JLayoutbase->getOptions() returns a JRegistry object when options parameter is a JRegistry object.
 [x] JLayoutbase->getOptions() returns a JRegistry object value using an array.
 [x] JLayoutbase->getOptions() returns a JRegistry object value using JRegistry.
 [x] JLayoutbase->resetOptions() and check options is empty.
 [x] Escaping special characters into html entities
 [x] Add one debug message to the queue
 [x] JLayoutBase->getDebugMessages() retrieves a list of debug messages in an array.
 [x] JLayoutBase->renderDebugMessages() returns string of messages separated by newline character.
 [x] JLayoutBase->render() returns an empty string.
Add Fixes suggested by Sebastian Bergmann
Merge pull request #1 from javigomez/jlayout-systemtests

Add Fixes suggested by Sebastian Bergmann
Merge pull request #4688 from Bakual/DeprecateP3P

Deprecate the P3P plugin and set it to disabled for new installations.
Don't access application class var directly
Merge pull request #4744 from wilsonge/patch-24

Don't access application class var directly
Merge pull request #4699 from roland-d/jlayout-systemtests

[Code Test] Implement tests for JLayout base
[fix] #4740 headers show when no record
Query fix in mod_articles_archive so it works in PostgreSQL. Fixes #3292
Modify JResponseJsonTest
Really fix it this time
Merge pull request #4749 from infograf768/usernotes

[fix] #4740 Users Notes: headers show when no record
Improvements to JSchemaChangesetTest
Merge branch 'staging' of github.com:joomla/joomla-cms into staging
Added events map property.

This allows for events to be mapped to plugin groups independently.
Synced with latest JModelAdmin changes.
Trigger extension save events on config save actions.
Trigger content save and delete events.
Consistency fix.