Merge pull request #165 from ekohl/respect-systemd-RUNTIME_DIRECTORY

Respect systemd's RUNTIME_DIRECTORY environment variable

Author: bastelfreak

lib/puppet/util/run_mode.rb

@@ -81,7 +81,7 @@ def public_dir
       end
 
       def run_dir
-        which_dir("/var/run/puppetlabs", "~/.puppetlabs/var/run")
+        ENV.fetch('RUNTIME_DIRECTORY') { which_dir("/var/run/puppetlabs", "~/.puppetlabs/var/run") }
       end
 
       def log_dir