imputation off all best matches plus removeSites and a few bits
add .PHONY to makefile so make test actually runs the tests
add ability to write out VCF using htslib
add test for writeVcf
changes to let tests pass since addition of aFend. also readSites file was not storing variation correctly
free allocated memory to keep valgrind happy
Merge pull request #4 from sm15/feature/write_vcf

new -writeVcf option