add 3.7, 3.8-dev and PyPy3.5 to travis

Author: nilsnolde

.travis.yml

@@ -1,10 +1,19 @@
+dist: xenial   # required for Python >= 3.7
 language: python
 
 python:
   - "2.7"
   - "3.4"
   - "3.5"
   - "3.6"
+  - "pypy3.5-6.0"
+
+matrix:
+  include:
+  - python: 3.7
+  - python: 3.8-dev
+    dist: xenial
+    sudo: true
 
 install:
   - pip install coverage

README.rst

@@ -74,18 +74,11 @@ By using this library, you agree to the ORS `terms and conditions`_.
 
 Requirements
 -----------------------------
-openrouteservice-py requires:
+openrouteservice-py is tested against CPython 2.7, 3.4, 3.5, 3.6, 3.7 and 3.8-dev, and PyPy3.5.
 
-- Python >= 2.7, 3.4, 3.5, 3.6, 3.7 (pip)
-- Python >= 2.7, 3.6, 3.7 (conda)
-- ``requests`` library
-- ``cerberus`` library
+For setting up a testing environment, install ``requirements-dev.txt``::
 
-Unit testing requires additionally the following Python libraries:
-
-- ``nose``
-- ``responses``
-- ``mock``
+    pip install -r requirements-dev.txt
 
 Installation
 ------------------------------