Added TransCount method for GRangesList

Now TransCount can operate on a GRanges list and will return a vector of same length as the GRangesList.  This vevtor will contain the count of transmissions for each GRange element.

It has one loop -- the loop through the GRangesList.  This couls surely be made more efficient with lapply in parallel somehow.
Created ScanTrio method

Also added some utility methods that operate on GRanges and GRangesList object.  These methods are coercion methods and probably can be improved with the help of savy GRanges coding.
Worked on the ScanTrio method

window names were added.
updated vignette