.travis.yml: Add pypy but allow fail

Conflicts:
	.travis.yml

.travis.yml

@@ -4,11 +4,16 @@ env:
     - TOXENV=cover3
     - TOXENV=py26
     - TOXENV=py27
-    # - TOXENV=pypy
+    - TOXENV=pypy
     - TOXENV=py32 # no u"" support
     - TOXENV=py33
-    # - TOXENV=py34 # No support on Travis-Ci at this time
+    - TOXENV=py34 # No support on Travis-Ci at this time
+matrix:
+  allow_failures:
+    - env: TOXENV=pypy
+    - env: TOXENV=py34
+  fast_finish: true
 install:
     - travis_retry pip install tox==1.6.1
 script:
-    - travis_retry tox
+    - travis_retry tox