comment out debug statements
minor refactor at Travis' suggestion
add unsignedDifference function

to avoid typing x >= y ? x - y : y - x or casting/abs all over the place
Merge branch 'master' of https://github.com/genome/joinx into homp-filter
stub in code for integration test for vcf-annotate-homopolymers
expected file for current test data
add feedback and fix typo in test