Add Guid support on primitive value collection mapping

[welbertwpg]

No description provided.

[welbertwpg]

You should consider this PR, which is very useful when you use Guid as PK instead of int or any other primitive type and you need to do a Select of this primary keys and map them in their primitive type, as you do on the I_Can_Map_Value_PrimitiveTyped_Collection and I_Can_Map_Value_SpecialStringTyped_Collection tests.

Anyway, thank you for this lib!