C++: add support for resolving typedefs for template arguments

Example:
template <typename T>
struct Base { T t; };
struct Foo { int foo; };
void fun() {
  typedef Foo TypedefedFoo;
  Base<TypedefedFoo> baseFoo;
  baseFoo.t.// no code completion
}

Change-Id: I4822693d3fa1ee2e9b0e4cdd28bb9a8d441fb313
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>