Use Cinc by default for knife-zero bootstraps

.chef/config.rb.example

@@ -12,3 +12,7 @@ local_mode                true # Chef local mode, replacing Solo
 # https://docs.chef.io/attribute_persistence/
 # Source of truth: site-cookbooks/kosmos-base/files/default/chef_attributes.rb
 client_d_dir(File.expand_path("../site-cookbooks/kosmos-base/files/default/chef_attributes.rb"))
+
+# Chef binaries on packages.chef.io are license-gated (HTTP 402); use the
+# community Cinc build for bootstraps and converged nodes.
+knife[:alter_project] = "cinc"