Fix user form

* fix issue with checkbox on user form
* use consistent style for const char pointers
* use unique hostname by default

lib/framework/FSPersistence.h

@@ -11,7 +11,7 @@ class FSPersistence {
                 JsonStateUpdater<T> stateUpdater,
                 StatefulService<T>* statefulService,
                 FS* fs,
-                char const* filePath,
+                const char* filePath,
                 size_t bufferSize = DEFAULT_BUFFER_SIZE) :
       _stateReader(stateReader),
       _stateUpdater(stateUpdater),
@@ -81,7 +81,7 @@ class FSPersistence {
   JsonStateUpdater<T> _stateUpdater;
   StatefulService<T>* _statefulService;
   FS* _fs;
-  char const* _filePath;
+  const char* _filePath;
   size_t _bufferSize;
   update_handler_id_t _updateHandlerId;