Add installers goal and note about custom types/paths
Add installers goal and note about custom types/paths

buildsample/installers,blesta/installers,potherca-contrib/installers,composer/installers,micaherne/installers,bluematt/composer-installers,QafooGalaxy/installer,monofone/ansible-installer,c9s/installers,beaver-dev/feather-installers,shipci/installers,kidaa/installers,KennisMeester/installers,dedalozzo/installers,ribrit/installers,corneltek/installers