widl: Add aliased types to the typelib for statements in the library block if the typedef itself doesn't need to be added.

Otherwise, the order of types in the typelib will be wrong or types
will be missing.

Spotted by Chris Robinson.

We added a #version line a while ago, so the line number for the
warning changed.

Detecting strings is a bit harder than just looking for the string
attribute, so make sure to use the function which has the purpose of
doing just that.

Fixes compilation of generated server/proxy code when a parameter has
both the [out] and [string] attributes.

The resolv.h header file won't compile without netinet/in.h being
included first.