Añadida la clase UnsharpMask, encargada del trabajo final
Added the following function prototypes to the class UnsharpMask

- setCutOffFrequency
- setOrderButterworth
- setGain
- getCutOffFrequency
- getOrderButterworth
- get Gain
- Default constructor
Implemented default constructor as inline method
Implemented setCutOffFrequency method as inline
Implemented setOrderButterworth as inline method
Implemented setGain as inline method
Implemented getCutOffFrequency as inline method
Implemented getOrderButterworth as inline method
Implemented getGain as inline method