Advanced %rename fixes for templates

It is now possible to use %rename
on instantiated templates for various corner cases, see "Template renaming"
section in SWIGPlus.html. For example, it is now possible to selectively rename
overloaded templated functions. The full power of %rename (such as using regex)
can now be used on templates.

Example fix using %rename on templates:
  namespace Quirky {
    template<typename T> void funky() {}
  }
  %rename("%s_void") Quirky::funky<int>();
  %template(funky_int) Quirky::funky<int>;
Will now generate funky_void() where previously there there was no wrapper, just
a warning:
    Warning 503: Can't wrap 'funky< int >_void' unless renamed to a valid identifier.