Version 0.13.3

• When clustering VCF records (as used by minos) proper handling of heterozygous genotypes. Previously if GT was N/M, N!=M, and N and M both non-zero, then the record would not get used. Now both alleles are added to the output.
• Fix to only use alleles that comprise A,C,G,T characters only. Other alleles now ignored, instead of making it to the output and breaking minos. This stops in particular alleles like <foo> getting used, which are allowed in the VCF spec.