ETC

There are some instrument/site specific cases for which the ETC-42 algorithm cannot calculate (yet) either the signal or the background noise by converting the instrument specific information to ETC-42 inputs (this raised during the EUCLID plugin development). To allow for easy development of plugins for these cases (which will allow for easy and fast calculation of the SNR without need of modification of the ETC-42) the ETC-42 can be extended to take into consideration some extra signal and background noise. The user should have the option to select if he wants to use the extra signal or background noise, the one calculated by the ETC-42 or a combination of the two.