Make Composer work with PHP 5.2 and earlier. Reported by @voku
Make Composer work with PHP 5.2 and earlier. Reported by @voku

Signed-off-by: Edward Z. Yang <dbd597f5635f432486c5d365e9bb585b3eaa1853@cs.stanford.edu>

Janson-Leung/htmlpurifier,r-kovalenko/htmlpurifier,Janson-Leung/htmlpurifier,ezyang/htmlpurifier,Janson-Leung/htmlpurifier,ezyang/htmlpurifier,stefanotorresi/htmlpurifier,stefanotorresi/htmlpurifier,r-kovalenko/htmlpurifier,bartbutler/htmlpurifier,bartbutler/htmlpurifier,bartbutler/htmlpurifier,r-kovalenko/htmlpurifier,bartbutler/htmlpurifier,stefanotorresi/htmlpurifier,ezyang/htmlpurifier,Masterjoa/HTMLPurifier-standalone,ezyang/htmlpurifier,Janson-Leung/htmlpurifier,r-kovalenko/htmlpurifier,Masterjoa/HTMLPurifier-standalone,stefanotorresi/htmlpurifier