Better io list

• Added IOList as replacement for plain dicts for inputs and outputs in Components.
• IOList behaves like a dict, but one can use the .add method to add Inputs/Outputs either by a class or name/info.
• Inputs/Outputs now need a name when created.
• IOList is freezable, so after initialize no IOs can be added.
• no items can be removed from IOList after they are added