Nullable, valued literals are not currently expressible

[jacques-n]

Right now, there is no way to express a nullable literal for non-null values. I think we need to introduce a "nullable" property on all literals.

For example, I want to create an i8? literal that is defined as 5. Right now, this is impossible. I can only declare an i8 of 5 or a i8? that is null. In a 2x2, the problem is the lower right below:

Category	No Value	With Value
Non-nullable	Typed Null Literal	Value Literal
Nullable	Typed Null Literal	Not Possible

While a bit arcane, this is important to express in strongly typed systems when trying to do a roundtrip.

[jacques-n]

Resolved in #88