add api to get/set footer and remove all use of custom.js

src/cloudron.js

@@ -33,11 +33,9 @@ var apps = require('./apps.js'),
     debug = require('debug')('box:cloudron'),
     domains = require('./domains.js'),
     eventlog = require('./eventlog.js'),
-    custom = require('./custom.js'),
     fs = require('fs'),
     mail = require('./mail.js'),
     notifications = require('./notifications.js'),
-    os = require('os'),
     path = require('path'),
     paths = require('./paths.js'),
     platform = require('./platform.js'),
@@ -136,7 +134,7 @@ function getConfig(callback) {
             isDemo: settings.isDemo(),
             provider: settings.provider(),
             cloudronName: allSettings[settings.CLOUDRON_NAME_KEY],
-            uiSpec: custom.uiSpec()
+            footer: allSettings[settings.FOOTER_KEY]
         });
     });
 }