Merge remote-tracking branch 'origin/3.0'

Conflicts:
	control/Cookie.php
	control/Director.php
	control/HTTPResponse.php
	model/Database.php
	model/MySQLDatabase.php
	model/SQLQuery.php
	view/Requirements.php
	view/SSViewer.php
Merge remote branch 'origin/master' into translation-staging
Updated translations master
Line length fixes
Merge remote branch 'origin/master' into translation-staging
Updated translations
Updated translations
Updated translations
Updated translations
NEW Add documentation for the new config system in 3.0
Merge pull request #840 from silverstripe-rebelalliance/config_system_docs

NEW Add documentation for the new config system in 3.0
Updated translations
Updated translations
ENHANCEMENT Make it possible to extend SS_Log

Using late static binding makes it possible to override SS_Log to create
logs which are separate to the main Silverstripe log but still use the
built in functionality.

Add test for SS_Log subclassing.
Merge pull request #841 from drzax/log-enhancement

ENHANCEMENT Make it possible to extend SS_Log
Updated translations
Updated translations
Updated translations
Updated translations
Updated translations