Remove type arguments and type abstractions from Nodes

[lukaszcz]

This should also adjust the types stored in the Infos and InfoTable, removing quantification over types and replacing all type variables with the dynamic type (see PR #1508).

For example,

\A : Type \f : ((B : Type) -> A -> B -> Pair A B) \x : A { f A x x }

should be transformed to

\f : (* -> * -> Pair * *) \x : * { f x x }

This transformation is a special case of a broader "runtime-irrelevance analysis" we might want to have later with dependent types.

Notes

• Depends on PR Dynamic type in Core #1508.
• Closing issue Parse optional type information in JVC files #1509 would help with debugging.