pass coveralls env

tox.ini

@@ -8,7 +8,6 @@ commands= py.test --lsof -rfsxX --junitxml={envlogdir}/junit-{envname}.xml []
 deps=
     nose
     mock
-passenv=COVERALLS_REPO_TOKEN
 
 [testenv:py27-subprocess]
 changedir=.
@@ -143,13 +142,15 @@ commands=
     {envpython} tox_run.py
 
 [testenv:coveralls]
-changedir=testing
+passenv = TRAVIS TRAVIS_JOB_ID TRAVIS_BRANCH
+changedir=
+usedevelop=True
 basepython=python3.4
 deps =
     {[testenv]deps}
     coveralls
 commands=
-    coverage run --source=_pytest {envdir}/bin/py.test
+    coverage run --source=_pytest {envdir}/bin/py.test testing
     coverage report -m
     coveralls