Fix RabbitMQ restart
    
    - Remove compatibility triggerun scriptlet
    - Don't wait for slave stop messages forever (patches #2, #3)
    - Drop dependency on syslog.target - this seems to be a leftover
    - Require epmd@0.0.0.0 to run. This is a default value. User should
      override it if necessary. This fixes rhbz #1302368.
    
    Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>