Back to pip install of the package to avoid ImportError:

`No module named 'zc.sourcefactory'`.

But now we do not install the docs extra and do not use sphinx to run doctests as there are none of such doctests which can only be run by Sphinx.

.travis.yml

@@ -6,11 +6,11 @@ python:
     - 3.4
     - 3.5
 install:
-    - pip install -U zc.buildout coverage coveralls
-    - buildout bootstrap
-    - buildout
+    - pip install -U pip setuptools
+    - pip install -U coverage coveralls
+    - pip install -U -e .[test]
 script:
-    - coverage run bin/test
+    - coverage run -m zope.testrunner --test-path=src
 after_success:
     - coveralls
 notifications: