VCFSTATS: Moved allelesCode y Genotype to vcf4 folder
VCFFILTERS: Added initial code to VCFFilters and added some tests
VCFFILTERS: Added guava predicates to method Vcf4Reader
VCFSTATS: Added genotypes to stats
VCFSTATS: Added transitions and transversions to Stats
VCFFILTERS: Rename the class VcfFilter