message: clarify how to use the CNV map
diff: @@ -126,11 +126,12 @@ void Parameters::usage(char** argv) {
  << " -A --cnv-map FILE" << endl
  << " Read a copy number map from the BED file FILE, which has" << endl
  << " either a sample-level ploidy:" << endl
  - << " sample name, copy number" << endl
  + << " sample_name copy_number" << endl
  << " or a region-specific format:" << endl
  - << " reference sequence, start, end, sample name, copy number" << endl
  + << " seq_name start end sample_name copy_number" << endl
  << " ... for each region in each sample which does not have the" << endl
  - << " default copy number as set by --ploidy." << endl
  + << " default copy number as set by --ploidy. These fields can be delimited" << endl
  + << " by space or tab." << endl
  << endl
  << "output:" << endl
  << endl
  