Make input prompt clearer in extract task.
Make input prompt clearer in extract task.

Make the prompt display the paths that will be scanned.  Hopefully
this makes the shell a bit easier to use and understand. Also
make the shell not accept 0 paths as a correct answer.

Fixes #2877

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