fixes ZEN-15510

add a DMD setting for zenossHostname.  This value is set during
quickstart and editable in the Advanced Tab.  The Email Action will
attempt to use the hostname in zenactiond.conf, then try
dmd.zenossHostname, then finally fall back to "localhost:8080"
remove debug
Changes from jhanson
Merge pull request #617 from zenoss/feature/ZEN-15510

fixes ZEN-15510 reviewed by jhanson