`examplevalues` property

[HaraldZealot via Digitalmars-d]

I found myself in situation that were good that all types support 
`.examplevalues` property in unittest version. This property will 
return array of predefined values for specified type (we can even 
have some convention like `examplevalues[0]` is `init`, 
`examplevalues[1]` is `min` (for numerical type) an so on). If 
custom types doesn't redefine this property the array consist 
only from `init`.

The use case for this: templated struct or class with 
container-like semantics and internal unittest for method of such 
class.

Thoughts?