Remove session.auto_start configuration.
Remove session.auto_start configuration.

It now fails in PHP >= 5.5.2 . Also it never did anything in earlier
versions as the session would have already been started if auto_start
was true.

Fixes #4010

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