Add manage_sshd conditional

Allow sshd configuration to be skipped on "special" machines using
an optional "manage_sshd: False" pillar option.

Signed-off-by: Georg Pfuetzenreuter <mail@georg-pfuetzenreuter.net>

salt/common/ssh.sls

@@ -1,5 +1,6 @@
 include:
   - openssh.banner
+{%- if salt['pillar.get']('manage_sshd', True) %}
   - openssh.config
 
 /etc/ssh/user_ca:
@@ -10,3 +11,4 @@ include:
       {%- endfor -%}
     - require:
       - pkg: openssh
+{%- endif %}