Unable to run tests locally.

I created a fork and tried to run the tests locally, but they fail. My steps:

```
virtualenv --no-site-packages --distribute venv
source venv/bin/activate
pip install -r dev-requirements.txt --allow-external progressbar --allow-unverified progressbar
pip install -r requirements.txt
script/test
```

Output:

```
(venv)>script/test
Traceback (most recent call last):
File "/Users/richard/Sites/dev/loom/venv/bin/pspec", line 9, in
load_entry_point('pspec==0.0.2', 'console_scripts', 'pspec')()
File "/Users/richard/Sites/dev/loom/venv/lib/python2.7/site-packages/pkg_resources.py", line 356, in load_entry_point
return get_distribution(dist).load_entry_point(group, name)
File "/Users/richard/Sites/dev/loom/venv/lib/python2.7/site-packages/pkg_resources.py", line 2431, in load_entry_point
return ep.load()
File "/Users/richard/Sites/dev/loom/venv/lib/python2.7/site-packages/pkg_resources.py", line 2147, in load
['__name__'])
File "/Users/richard/Sites/dev/loom/venv/lib/python2.7/site-packages/pspec/__init__.py", line 2, in
from .collectors import run
File "/Users/richard/Sites/dev/loom/venv/lib/python2.7/site-packages/pspec/collectors.py", line 2, in
from attest.utils import import_dotted_name, deep_get_members
ImportError: No module named utils
```

Any ideas? Maybe `attest` needs to be pinned in dev-requirements.txt?

Start with dev-requirements.txt and script/test, then reproduce the listed virtualenv setup and failing command. Inspect the installed attest and pspec dependency versions around the missing utils import. Done means the documented setup completes and script/test runs successfully.

Written by the indexing model from the issue text.