Merge pull request #84 from SylvainDe/master

Add most recent Python versions in Travis CI

.travis.yml

@@ -1,8 +1,19 @@
 language: python
 python:
+  - "nightly"
+  - "3.7-dev"
+  - "3.6-dev"
+  - "3.6"
+  - "3.5"
   - "3.4"
   - "3.3"
   - "2.7"
+matrix:
+  fast_finish: true
+  allow_failures:
+    - python: "nightly"
+    - python: "3.7-dev"
+    - python: "3.6-dev"
 install:
   - pip install --install-option='--no-cython-compile' Cython
   - pip install -r dev_requirements.txt