Re-enable other tests again. [skip ci]

.travis.yml

 language: python
 sudo: false
 python:
-#    - 2.6
+    - 2.6
     - 2.7
-#    - pypy
-#    - 3.3
-#    - 3.4
-#    - 3.5
+    - pypy
+    - 3.3
+    - 3.4
+    - 3.5
 env:
     - LINT=true
     - LINT=false

Makefile

@@ -98,10 +98,6 @@ travis_cpython:
 travis_test_linters:
 	make lint
 	GEVENTTEST_COVERAGE=1 make leaktest
-# XXX Can we do this here? It would be nice to get these reports, but
-# first, it may cause issues with the leak tests. And second, 'coverage combine'
-# chokes if a datafile hasn't been fully written, which can happen when
-# our timeout killer kills a script (and they do take longer under coverage)
 	coverage combine
 	coveralls