- added a new option: 'options.center' to .setVisible, will center the item in view when TRUE;
- added the 'persist' extension: a way to save/restore item states (open/selected) using local storage (jStorage plugin is used, depends on the 'utils' extension for item searching by ID);
- added the 'hash' extension: a way to parse item states (open/selected) from the URL fragment (aciFragment plugin is used, depends on the 'utils' extension for item searching by ID);
- typo bug fix: .edit & .select used 'this' instead of 'item' for the first parameter of the success/fail callbacks.