fix(mod_ssl): update mod_ssl package variable to prevent clashes

The mod_ssl package name could be overridden in apache:lookup:mod_ssl.
Due to the way lookup keys are merged into the main apache dictionary,
the package name clashed with the mod_ssl configuration defined under
apache:mod_ssl.

Fix that by renaming the mod_ssl package variable to mod_ssl_pkg.

Drive-By: Add mod_ssl_pkg to the pillar.example file.

apache/mod_ssl.sls

 
 mod_ssl:
   pkg.installed:
-    - name: {{ apache.mod_ssl }}
+    - name: {{ apache.mod_ssl_pkg }}
     - require:
       - pkg: apache
     - watch_in:

apache/osfamilymap.yaml

   group: apache
   configfile: /etc/httpd/conf/httpd.conf
 
-  mod_ssl: mod_ssl
+  mod_ssl_pkg: mod_ssl
   mod_wsgi: mod_wsgi
   conf_mod_wsgi: /etc/httpd/conf.d/wsgi.conf
   mod_php5: php

pillar.example

     # apache version (generally '2.2' or '2.4')
     version: '2.2'
 
+    # mod_ssl package name
+    mod_ssl_pkg: mod_ssl
+
     # ``apache.mod_wsgi`` formula additional configuration:
     mod_wsgi: mod_wsgi