fix '~' completion in add folder (fix #1478)

AUTHORS

@@ -21,6 +21,7 @@ Emil Hessman <emil@hessman.se>
 Federico Castagnini <federico.castagnini@gmail.com>
 Felix Ableitner <me@nutomic.com>
 Felix Unterpaintner <bigbear2nd@gmail.com>
+Francois-Xavier Gsell <fxgsell@gmail.com>
 Gilli Sigurdsson <gilli@vx.is>
 Jakob Borg <jakob@nym.se>
 James Patterson <jamespatterson@operamail.com> <jpjp@users.noreply.github.com>

gui/scripts/syncthing/core/controllers/syncthingController.js

@@ -901,6 +901,9 @@ angular.module('syncthing.core')
         $scope.directoryList = [];
 
         $scope.$watch('currentFolder.path', function (newvalue) {
+            if (newvalue && newvalue.trim().charAt(0) == '~') {
+                $scope.currentFolder.path = $scope.system.tilde + newvalue.trim().substring(1)
+            }
             $http.get(urlbase + '/system/browse', {
                 params: { current: newvalue }
             }).success(function (data) {