add a unit test for arast.py

Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
Merge branch 'master' into issue-49
Merge branch 'master' of https://github.com/kbase/assembly into issue-49
update dependency list

Link: https://github.com/kbase/assembly/issues/133
Signed-off-by: Sébastien Boisvert <boisvert@anl.gov>
Merge pull request #142 from sebhtml/issue-49

Issue 49