Splinecloud-scipy

- Add method load data that was used to construct spline
- Updated Examples
- Bug fixes

- Add an option to evaluate extrapolated values.
- Construct spline object in a conventional way (breaks backward compatibility).
Now to instantiate the spline, simply call `ParametricUnivariateSpline(tcck)`

Add spline fitting accuracy calculation using the next methods:
- RSME: root mean square error
- MSE: mean square error
- MAE: mean absolute error

First release