Supplies getter and setter callbacks across all the properties along with a for(x in y) callback that returns the list

Callback's can use the _this_ object in order to act normally without reinvoking themselves.

** Value onGet(String propertyName, Value value, hadAlready)

Returns the value at a specific index

** Value onSet(String propertyName, Value oldValue, Value value, hadAlready)

Returns the value to save at a specific index

** Array onForeach()

Returns an array containing all the index keys for this object