Make parent method check explicit to Shell.
Make parent method check explicit to Shell.

This makes only methods on Shell inaccessible on the command line.
Parent methods in AppShell or other parent classes can now be called directly.
Fixes #2193

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