SemanticMediaWiki/SemanticMediaWiki — pull request #85 by mwjames (2014-01-06 14:13:30+00:00)
Title: JSON_PRETTY_PRINT introduced with PHP 5.4

Apparently JSON_PRETTY_PRINT option was only introduced with PHP 5.4
therefore we use FormatJson::encode() which does pretty print in PHP 5.3