Make the REPL show value type name

[marad]

This will probably require adding type information to truffle value nodes.

• Add type information to all nodes
• Maybe IsNode could use the type information

[marad]

Adding type information to truffle nodes is time consuming and now it's not the best time to do so. It would be better to first do #62 since it also requires changing how AST conversions work.

Alternatively I could simply add 'typeOf' node that evaluates result and returns Type based on specialization. It could return module, package, type name and concrete type parameters as ChiObject with those fields.