1. Modified vcf_parse to update rlen only when an END INFO tag is seen -
the END tag is NOT encoded into v->shared.s
2. Modified vcf_write to add END INFO tag if required:
Add END iff rlen != strlen(reference)
FIXME: what happens when rlen == strlen(reference)? Conditions for
adding END are unclear
Merge pull request #5 from broadinstitute/intel_remove_END

1. Modified vcf_parse to update rlen only when an END INFO tag is seen -