Infinite recursion in set_status(http::status_code::value, const std::string&) in develop branch

The set_status function overload calls itself in https://github.com/zaphoyd/websocketpp/blob/b9aeec6eaf3d5610503439b4fae3581d9aff08e8/websocketpp/impl/connection_impl.hpp#L595
This is due to missing third argument. It is:
```cpp
this->set_status(code, msg);
```
but IMO it should be:
```cpp
this->set_status(code, msg, ec);
```