enable Finder on Cinnamon

lib/main-app.js

@@ -288,6 +288,14 @@ app.on('ready', function () {
       })
       break
     case 'linux':
+      if (process.env.DESKTOP_SESSION === 'cinnamon') {
+        finderWindow = require('./finder-window')
+        finderWindow.on('close', function (e) {
+          if (appQuit) return true
+          e.preventDefault()
+          finderWindow.hide()
+        })
+      }
       // Do nothing.
   }