Prepare to write unit tests

.travis.yml

@@ -0,0 +1,20 @@
+dist: trusty
+sudo: false
+
+language: python
+python:
+  - "2.7"
+  - "3.4"
+  - "3.5"
+  - "3.6"
+
+install:
+  - pip install -r requirements.txt
+  - pip install pytest pytest-cov codecov flake8
+
+script:
+  - pytest --cov=webssh
+  - flake8 --exclude='.git'
+
+after_success:
+  - codecov