use path separator for output dir
use path separator for output dir

srawlins/dartdoc,keertip/dartdoc,d2m/dartdoc-2015,keertip/dartdoc,astashov/dartdoc,jakemac53/dartdoc,dart-lang/dartdoc,jakemac53/dartdoc,dart-lang/dartdoc,keertip/dartdoc,d2m/dartdoc-2015,a14n/dartdoc,d2m/dartdoc-2015,jakemac53/dartdoc,srawlins/dartdoc,dart-lang/dartdoc,a14n/dartdoc,srawlins/dartdoc,astashov/dartdoc,jakemac53/dartdoc,dart-lang/dartdoc,astashov/dartdoc,keertip/dartdoc,a14n/dartdoc,astashov/dartdoc,d2m/dartdoc-2015,srawlins/dartdoc