examples: laptop: add i3-mode

Closes #27

examples/configurations/laptop.conf

@@ -45,6 +45,15 @@ bar:
           - urgent: &urgent
               foreground: 000000ff
               deco: {stack: [background: {color: bc2b3fff}, <<: *std_underline]}
+          - map: &i3_mode
+              tag: mode
+              default:
+                - string:
+                    text: "{mode}"
+                    deco: {background: {color: cc421dff}}
+                - empty: {right-margin: 7}
+              values:
+                default: {empty: {}}
         content:
           "":
             map:
@@ -100,11 +109,14 @@ bar:
               left-margin: 7
               tag: application
               values:
-                "": {string: {text: "{title}"}}
+                "":
+                  - map: {<<: *i3_mode}
+                  - string: {text: "{title}"}
               default:
                 list:
                   spacing: 0
                   items:
+                    - map: {<<: *i3_mode}
                     - string: {text: "{application}", max: 10, foreground: ffa0a0ff}
                     - string: {text: ": "}
                     - string: {text: "{title}", max: 35}