middleman: add page (#3880)

pages/common/middleman.md

@@ -0,0 +1,28 @@
+# middleman
+
+> Static site generator written in Ruby.
+> More information: <https://middlemanapp.com/>.
+
+- Install the Middleman gem:
+
+`gem install middleman`
+
+- Create a new Middleman project:
+
+`middleman init "{{project_name}}"`
+
+- Start local server for current project on port 4567:
+
+`middleman server`
+
+- Start local server for current project on a specified port:
+
+`middleman server -p "{{port}}"`
+
+- Build your project to prepare to deploy:
+
+`bundle exec middleman build`
+
+- Deploy your Middleman project:
+
+`middleman deploy`