ci: Add Python 3.8 support (#254)

Author: mnoman09

.gitignore

@@ -1,8 +1,7 @@
 *.pyc
 MANIFEST
 .idea/*
-.virtualenv/*
-.py3virtualenv/*
+.*virtualenv/*
 
 # Output of building package
 *.egg-info

.travis.yml

@@ -5,6 +5,7 @@ python:
   - "3.5.5"
   - "3.6"
 # - "3.7" is handled in 'Test' job using xenial as Python 3.7 is not available for trusty.
+# - "3.8" is handled in 'Test' job using xenial as Python 3.8 is not available for trusty.
   - "pypy"
   - "pypy3"
 install: "pip install -r requirements/core.txt;pip install -r requirements/test.txt"
@@ -71,3 +72,8 @@ jobs:
         srcclr: true
       dist: xenial
       python: "3.7"
+    - stage: 'Test'
+      addons:
+        srcclr: true
+      dist: xenial
+      python: "3.8"

requirements/test.txt

@@ -1,4 +1,4 @@
-coverage==4.0.3
+coverage>=4.0.3
 flake8==3.6.0
 funcsigs==0.4
 mock==1.3.0