Remove release and unrelease
released -> is_released
add genome_build parameter to Query objects
add new GenomicFilter for range and position filters on genomic datasets
Merge pull request #65 from solvebio/feature/rangefilter

add new GenomicFilter for range and position filters on genomic datasets
Merge branch 'dev' into feature/netrc

Conflicts:
	solvebio/test/test_dataset.py