Add python3.7 (#115)

* Add python3.7-dev

* 3.7 is supported

* Add xenial

Author: be-hase

.travis.yml

@@ -1,10 +1,13 @@
+dist: xenial
+
 language: python
 
 python:
   - "2.7"
   - "3.4"
   - "3.5"
   - "3.6"
+  - "3.7"
 
 install: pip install tox-travis
 

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py27, py34, py35, py36, py36-flake8-src, py36-flake8-other
+envlist = py27, py34, py35, py36, py37, py37-flake8-src, py37-flake8-other
 
 [testenv]
 deps =
@@ -8,21 +8,21 @@ deps =
     -r{toxinidir}/requirements-test.txt
 commands = py.test -v tests/
 
-[testenv:py36]
-basepython = python3.6
+[testenv:py37]
+basepython = python3.7
 deps = {[testenv]deps}
 commands = py.test -v --cov=linebot tests/
 
-[testenv:py36-flake8-src]
-basepython = python3.6
+[testenv:py37-flake8-src]
+basepython = python3.7
 deps =
     six
     flake8
     flake8-docstrings
 commands = flake8 linebot/
 
-[testenv:py36-flake8-other]
-basepython = python3.6
+[testenv:py37-flake8-other]
+basepython = python3.7
 deps =
     six
     flake8