some dually windows and some not: error

[ChrisHIV]

If some MultipleInfections.InWindow_*.csv files are empty and some are not, DualPatientBlacklister.R breaks. The empty files go get skipped at the point

    if(file.size(file.name) == 0){
      cat('Skipping file ',file.name,' as it is empty\n')
    }

but later on there are two iterations over all suffices, each one with a call to read.table(). One of these calls crashes because it sees an empty file.

[ChrisHIV]

*do get skipped, not go get skipped.

[mdhall272]

Hopefully fixed.