v19

• Fixed obscure bug when placing an expectation using a value implicitly
  convertible to the target type, but not equal comparable with it.

  Example:

        struct S
        {
          S(const char* s_) : s(s_) {}
          bool operator(const char*) = delete;
          bool operator==(const S& rh) const
          {
            return s == rh.s;
          }
          std::string s;
        };
  
        struct mock {
          MAKE_MOCK1(func, void(S));
        };
  
        TEST(...)
        {
          mock m;
          REQUIRE_CALL(m, func("string"));
          // now compiles and compares the function call parameter value
          // with S("string")
        }

• Improved compilation error messages for type-mismatch situations in .RETURN()