Gk browser editing arrays

Makes it possible to 

*add or delete one or more object in a table
*create and insert one or more objects at selected rows in array
*remove one or more objects from array at selected rows
*ditto plus delete
*move one or more objects within an array by dragging

The created objects are filled with default values set in my code. Should probably check if defaults exist for the classes and use that when possible. The logic for letting the browser produce the default values is that the user might want to customise this, and the browser user might not have access to the model classes.

I know this is a big merge, but there isn't really any good way to split it into smaller merges. I will provide a  flow chart for the actions, since each interaction involves around half a dozen methods in 3 or 4 classes.
That's the approach I used first (which is incidentally why they are instance methods - I kept a counter for the int to avoid calling maxofproperty) but I changed it for two separate reasons: for strings someone felt that random string would seem confusing to the user and my solution to that was this more descriptive version. For ints the idea was that they might be using very large ints for the key (close to overflow), making the max + 1 business more complex too. But I would be happy to change the approach if you feel it is better!