Add type alias

[matter123]

Adds a type_alias pattern and tests. Extracted from #135.

[jeff-hykin]

If you can add some unit tests to :type_alias, I'll go ahead and merge it in. (I would do it, but I'm not sure exactly what is valid/invalid)

I still don't fully understand the :qualified_type pattern but I'll figure it out later

[matter123]

Sure.

[matter123]

The unit tests aren't quite sufficient yet

[matter123]

Ok, unit test added and all tests pass.

[matter123]

So :qualified_type is supposed to match a fully storage, namespace, and template qualified type.
that is struct A::B::C::D or std::enable_if<std::numeric_limit<long long int>::digits > 10, bool> It doesn't match type qualifiers like const or static or restrict, or type modifiers like ** and & so that it can be used in more places. The hope/plan is that much in the same way variable_name is used anywhere a name is expected, qualified_type is used whenever a type is expected.