Simplify apache::vhost::serveraliases logic

The data type does not allow a value that evaluates to false so no need
ot check for it.

Author: ekohl

manifests/vhost.pp

@@ -2551,7 +2551,7 @@
 
   # Template uses:
   # - $serveraliases
-  if $serveraliases and ! empty($serveraliases) {
+  if ! empty($serveraliases) and $ensure == 'present' {
     concat::fragment { "${name}-serveralias":
       target  => "${priority_real}${filename}.conf",
       order   => 210,

templates/vhost/_serveralias.erb

@@ -1,4 +1,4 @@
-<% if @serveraliases and ! @serveraliases.empty? -%>
+<% unless @serveraliases.empty? -%>
 
   ## Server aliases
   <%- Array(@serveraliases).each do |serveralias| -%>