Fix the Init Remote Folder field on SMB Bookmarks

If you set the Init Remote Folder field on an SMB Bookmark to a subfolder inside a share, i.e. customers\\active, and save it the result inside the field is customers\active which works. The problem is when you edit the bookmark but don't change that field it only has one \ and when saved the \ gets dropped leaving you with customersactive which obviously won't work. Some code needs to be added to look for a \ in that field and upon editing change it back to the required \\ so users don't have to pay attention to something they aren't even changing.