Add initial kosmos-postgresql cookbook

This is to install PostgreSQL all in one place instead of for each
service that needs it (Mastodon, ejabberd, ...)

site-cookbooks/kosmos-postgresql/.gitignore

@@ -0,0 +1,22 @@
+.vagrant
+*~
+*#
+.#*
+\#*#
+.*.sw[a-z]
+*.un~
+
+# Bundler
+Gemfile.lock
+gems.locked
+bin/*
+.bundle/*
+
+# test kitchen
+.kitchen/
+.kitchen.local.yml
+
+# Chef
+Berksfile.lock
+.zero-knife.rb
+Policyfile.lock.json