SASL authentication fails

[Jean-Baptiste Lernout]

SASL authentication doesn't work.

When connecting to a server using SASL, we have the following callstack :
- memcached_connect
- memcached_sasl_authenticate_connection
- memcached_response
- _read_one_response

in function _read_one_response, during SASL authentication, the rc value is set to MEMCACHED_AUTH_CONTINUE.

This value is not considered as a success by memcached_fatal which result in closing the connection to memcached, preventing the authentication to complete properly.

the memcached_fatal function should look like this :

static inline bool memcached_fatal(memcached_return_t rc)
{
  return (
          rc != MEMCACHED_BUFFERED &&
          rc != MEMCACHED_CLIENT_ERROR &&
          rc != MEMCACHED_DATA_EXISTS &&
          rc != MEMCACHED_DELETED &&
          rc != MEMCACHED_E2BIG &&
          rc != MEMCACHED_END &&
          rc != MEMCACHED_ITEM &&
          rc != MEMCACHED_ERROR &&
          rc != MEMCACHED_NOTFOUND &&
          rc != MEMCACHED_NOTSTORED &&
          rc != MEMCACHED_SERVER_MEMORY_ALLOCATION_FAILURE &&
          rc != MEMCACHED_STAT &&
          rc != MEMCACHED_STORED &&
          rc != MEMCACHED_SUCCESS &&
          rc != MEMCACHED_VALUE &&
          rc != MEMCACHED_AUTH_CONTINUE);
}