Additional Peak detector options

There are two additional peak detector options supported by the GUI and the underlying software

a) It is now possible to specify separate window sizes for the positive and negative alignments. A larger window size for the negative alignments makes the results less susceptible to the increased noise that it is often seen in the negative alignments. A window size of 400 has been found to give better results than the default of 100

b) It is possible to extend the boundary that is found by a fixed amount on both sides (window b). There is less need for this feature now that larger window sizes for the negative alignments have been introduced.