Plan ModelInfo replacement

[baseTwo]

CQL additions for operators, define types in cql, base type library for cql in cql.

[ewoutkramer]

There are two parts to it:

• The public discussion on what this should look like in CQL
• What our internal representation looks like.

When we will start #2 before we have #1, we might need to re-align when the public discussion is done. So we'll make do with our current xml-based modelinfo classes.