syslog support

[jfryman]

This PR adds Syslog support to the Puppet module. Adds five new attributes to st2:

#  [*syslog*]             - Routes all log messages to syslog
#  [*syslog_host*]        - Syslog host. Default: localhost
#  [*syslog_protocol*]    - Syslog protocol. Default: udp
#  [*syslog_port*]        - Syslog port. Default: 514
#  [*syslog_facility*]    - Syslog facility. Default: local7