Development branch merged to master

After email from Anne, to allow her to test her script
I will keep working on the development branch, which currently does not handle single reader Excel files properly
Apart from above error, this PR corrects errors in toyFiles and the new DfReadDataFile() function and related files and passes R CMD checks
Additional members added to dataset object
File affected: DfReadDataFile() and checkTruthTable.R
This is to make it easier to correlate the NL and LL values with those in the Excel file and catch data entry errors
Additional members:

design = design,
normalCases = normalCases,
abnormalCases = abnormalCases,
truthTableStr = truthTableStr

Need to update all dataset objects and check all occurences where DfReadDataFile() is used

dpc10ster / RJafroc