Added a NEWS.md file to track changes to the package.
Renaming:
xT for trace sample (instead of xD)
xR for reference sample (instead of xS)
Include functionality for sample specific error rates:
wT for Trace sample and wR for Reference sample
Convention: postfix _w for same error rate in both samples and postfix _wTwR to allow for different error rates in donor (trace) and suspect (reference) sample.
Added functions and objects related to sample specific error probabilities: