Added abstract 'columns' property to table

[PvdBerg1998]

No description provided.

[edvin]

This isn't a good solution to the reflection problem because it adds boilerplate. A better approach would be to have definitions themselves actually add the columns to the columns list. Then we could keep the columns list internal as well.

[PvdBerg1998]

I'd still prefer more boilerplate over reflection, but if there is a cleaner way ... I'm trying to add the column to a list inside of the Table.column function, but I can't figure out how to get the instance out of the delegate.

[edvin]

You can, but unfortunately not until the property is accessed. Therefor I think we need to skip the delegate and use a function instead.

[edvin]

Great! This is the right move!