Disable coverage during CI runs (#2328)

* Disable coverage during CI runs until we can figure out how to make it not such a performance penalty

* Remove after_success clause.

Author: cpennington

.travis.yml

@@ -13,9 +13,4 @@ install:
   - python setup.py install
 
 script:
-  - coverage erase
-  - python runtests.py --coverage
-  - coverage combine
-
-after_success:
-  - bash <(curl -s https://codecov.io/bash)
+  - python runtests.py