Update version number to 3.1.5
Update version number to 3.1.5

garethellis36/cakephp,mvdriel/cakephp,thinkingmedia/cakephp,CVO-Technologies/cakephp,elboletaire/cakephp,garethellis36/cakephp,nrother/cakephp,ionas/cakephp,ndm2/cakephp,gmponos/cakephp,gmponos/cakephp,CVO-Technologies/cakephp,ADmad/cakephp,tenkoma/cakephp,HavokInspiration/cakephp,ndm2/cakephp,berrygoudswaard/cakephp,justinyost/cakephp,tenkoma/cakephp,mvdriel/cakephp,CakeDC/cakephp,garethellis36/cakephp,petteyg/cakephp,jeffblack360/cakephp,Phillaf/cakephp,ADmad/cakephp,CVO-Technologies/cakephp,dkarvounaris/cakephp,elboletaire/cakephp,bravo-kernel/cakephp,dakota/cakephp,ndm2/cakephp,michaelze/cakephp,ionas/cakephp,garethellis36/cakephp,elboletaire/cakephp,cakephp-fr/cakephp,tgr0ss/cakephp,dakota/cakephp,ADmad/cakephp,davidyell/cakephp,timhoeppner/cakephp,nrother/cakephp,bravo-kernel/cakephp,ionas/cakephp,CakeDC/cakephp,cakephp/cakephp,HavokInspiration/cakephp,michaelze/cakephp,CakeDC/cakephp,tenkoma/cakephp,justinyost/cakephp,jeffblack360/cakephp,nrother/cakephp,cakephp/cakephp,tgr0ss/cakephp,timhoeppner/cakephp,petteyg/cakephp,eryw/cakephp,thinkingmedia/cakephp,davidyell/cakephp,cakephp/cakephp,dakota/cakephp,thinkingmedia/cakephp,timhoeppner/cakephp,justinyost/cakephp,dkarvounaris/cakephp,bravo-kernel/cakephp,tgr0ss/cakephp,ADmad/cakephp,petteyg/cakephp,berrygoudswaard/cakephp,HavokInspiration/cakephp,cakephp/cakephp,jeffblack360/cakephp,eryw/cakephp,petteyg/cakephp,Phillaf/cakephp,ndm2/cakephp,cakephp-fr/cakephp,eryw/cakephp,davidyell/cakephp,mvdriel/cakephp,dkarvounaris/cakephp,cakephp-fr/cakephp,gmponos/cakephp,Phillaf/cakephp,dakota/cakephp,mvdriel/cakephp,berrygoudswaard/cakephp,tenkoma/cakephp,michaelze/cakephp,CakeDC/cakephp