Improve recognition of template definitions.

In the long run, this will probably be better fixed by a proper
expression parser..

Before:
  template <typename F>
  Matcher(const Matcher<F> & Other,
          typename enable_if_c < is_base_of<F, T>::value &&
              !is_same<F, T>::value > ::type * = 0)
      : Implementation(new ImplicitCastMatcher<F>(Other)) {}

After:
  template <typename F>
  Matcher(const Matcher<F> & Other,
          typename enable_if_c<is_base_of<F, T>::value &&
                               !is_same<F, T>::value>::type * = 0)
      : Implementation(new ImplicitCastMatcher<F>(Other)) {}