Put coverage config in setup.cfg

One less top level file

Author: RazerM

.coveragerc

@@ -7,3 +7,15 @@ skip = ./build, ./docs
 not_skip = __init__.py
 # ci/travis.sh installs outcome normally, so isort assumes it's third party
 known_first_party = outcome
+
+[coverage:run]
+branch = True
+source =
+    outcome
+    tests/
+
+[coverage:report]
+precision = 1
+exclude_lines =
+    pragma: no cover
+    abc.abstractmethod