Wrong default replacement values

[borongyuan]

Hi,
I found the default value of lower_replacement_value and upper_replacement_value in LaserScanRangeFilter is 0, not NaN.
This is caused by the implementation of getParam().

bool getParam(const std::string & name, double & value)
  {
    return getParamImpl(name, rcl_interfaces::msg::ParameterType::PARAMETER_DOUBLE, 0.0, value);
  }

This may also affect other filters.