Fix for UpgradeShell::helpers() not discovering core helpers.
Fix for UpgradeShell::helpers() not discovering core helpers.

web-player/cakephp,HavokInspiration/cakephp,jeffblack360/cakephp,bravo-kernel/cakephp,cakephp/cakephp,CVO-Technologies/cakephp,Balachan27/cakephp,elboletaire/cakephp,tgr0ss/cakephp,cakephp/cakephp,et304383/passbolt_api,akintoey/cakephp,berrygoudswaard/cakephp,tisu2tisu/cakephp,erikfig/cakephp,jeffblack360/cakephp,mvdriel/cakephp,davidyell/cakephp,khoimt/cakephp-study,garethellis36/cakephp,petteyg/cakephp,eboominathan/cakephp,justinyost/cakephp,CakeDC/cakephp,tgr0ss/cakephp,berrygoudswaard/cakephp,davidyell/cakephp,ADmad/cakephp,nrother/cakephp,akintoey/cakephp,mvdriel/cakephp,thinkingmedia/cakephp,gmponos/cakephp,et304383/passbolt_api,nrother/cakephp,ADmad/cakephp,garethellis36/cakephp,burriko/cakephp,justinyost/cakephp,eryw/cakephp,thinkingmedia/cakephp,ndm2/cakephp,et304383/passbolt_api,ndm2/cakephp,ADmad/cakephp,berrygoudswaard/cakephp,tisu2tisu/cakephp,adopico/cakephp,cakephp/cakephp,jerems02/cakephp,jerems02/cakephp,tenkoma/cakephp,gmponos/cakephp,pbaire/cakephp,dkarvounaris/cakephp,yinhe007/cakephp,yinhe007/cakephp,jerems02/cakephp,pbaire/cakephp,ndm2/cakephp,bravo-kernel/cakephp,akintoey/cakephp,adopico/cakephp,CVO-Technologies/cakephp,et304383/passbolt_api,timhoeppner/cakephp,Phillaf/cakephp,jjj117/cakephp,petteyg/cakephp,michaelze/cakephp,burriko/cakephp,elboletaire/cakephp,dkarvounaris/cakephp,tenkoma/cakephp,kumamidori/cakephp,jjj117/cakephp,dakota/cakephp,cakephp/cakephp,ionas/cakephp,jeffblack360/cakephp,CakeDC/cakephp,eboominathan/cakephp,garethellis36/cakephp,erikfig/cakephp,Phillaf/cakephp,cakephp-fr/cakephp,petteyg/cakephp,davidyell/cakephp,khoimt/cakephp-study,mvdriel/cakephp,Balachan27/cakephp,timhoeppner/cakephp,dakota/cakephp,petteyg/cakephp,bravo-kernel/cakephp,gmponos/cakephp,burriko/cakephp,tenkoma/cakephp,michaelze/cakephp,HavokInspiration/cakephp,tenkoma/cakephp,CakeDC/cakephp,pbaire/cakephp,kumamidori/cakephp,yinhe007/cakephp,Phillaf/cakephp,eryw/cakephp,nrother/cakephp,justinyost/cakephp,cakephp-fr/cakephp,dakota/cakephp,erikfig/cakephp,garethellis36/cakephp,tgr0ss/cakephp,thinkingmedia/cakephp,cakephp-fr/cakephp,ionas/cakephp,ionas/cakephp,CakeDC/cakephp,Balachan27/cakephp,web-player/cakephp,elboletaire/cakephp,web-player/cakephp,eryw/cakephp,jjj117/cakephp,HavokInspiration/cakephp,dakota/cakephp,ADmad/cakephp,khoimt/cakephp-study,michaelze/cakephp,timhoeppner/cakephp,mvdriel/cakephp,ndm2/cakephp,adopico/cakephp,dkarvounaris/cakephp,kumamidori/cakephp,tisu2tisu/cakephp,et304383/passbolt_api,eboominathan/cakephp,CVO-Technologies/cakephp