Remove SIMPLEPIE_PHP5 constant
Remove SIMPLEPIE_PHP5 constant

This was used for compatibility functions, and was an internal constant.
If you're using this in your own code, it's probably broken by now
anyway. :)

wikidi/simplepie,Alkarex/simplepie,ropik/simplepie,simplepie/simplepie,barryvdh/simplepie,barryvdh/simplepie,wikidi/simplepie,ropik/simplepie,skyzyx/simplepie,barryvdh/simplepie,FreshRSS/simplepie,wikidi/simplepie,blat/simplepie,songfj/simplepie,skyzyx/simplepie,blat/simplepie,mblaney/simplepie,Alkarex/simplepie,songfj/simplepie,songfj/simplepie,simplepie/simplepie,blat/simplepie,mblaney/simplepie,FreshRSS/simplepie,Alkarex/simplepie