Add option to configure PlantUML endpoint

bin/gollum

@@ -162,7 +162,6 @@ MSG
   end
   
   opts.separator ""
-  
 end
 
 # Read command line options into `options` hash
@@ -208,6 +207,7 @@ if options[:irb]
     if !wiki.exist? then
       raise Gollum::InvalidGitRepositoryError
     end
+
     puts
     puts "Loaded Gollum wiki at:"
     puts "#{File.expand_path(gollum_path).inspect}"
@@ -243,6 +243,13 @@ else
     require cfg
   end
 
+  if wiki_options[:plantuml_url]
+    Gollum::Filter::PlantUML.configure do |config|
+      puts "Using #{wiki_options[:plantuml_url]} as PlantUML endpoint"
+      config.url = wiki_options[:plantuml_url]
+    end
+  end
+
   base_path = wiki_options[:base_path]
 
   if base_path.nil?