fix also python-coverage

the new coverage package breaks API so pin it to version that works with
coveralls

1 files changed, 1 insertions, 1 deletions

diff --git a/tox.ini b/tox.ini
index 23d401f..4c2b030 100644
--- a/tox.ini
+++ b/tox.ini
@@ -31,7 +31,7 @@ deps =
      py: pytest
      py: hypothesis
      py{33}: wheel<0.30
-     coverage
+     coverage==4.5.4
 commands = coverage run --branch -m pytest {posargs:src/ecdsa}
 
 [testenv:py27_old_gmpy]