Refactor to_data and data method in all Action class , use attribute dict

[yck011522]

It would be good refactor the attribute storing method of the Action classes to be similar to the compas.datastructures attributes dictionary. Where the base class Action serialize the attributes dictionary, child classes can simply write getter and setter that points to an entry in that dictionary.

It will have a cleaner class signature, avoids each child class managing a chain of overriding data() while still having to call super class's data(). Especially in multiple inheritance scenarios.