setup travis

.travis.yml

+dist: trusty
+sudo: required
+language: python
+
+before_install:
+  - sudo add-apt-repository -y ppa:mc3man/trusty-media
+  - sudo apt-get update
+  - sudo apt-get install -y ffmpeg
+
+install:
+  - pip install opencv-python pyyaml codecov
+
+cache:
+  pip: true
+
+env:
+  global:
+    - COLUMNS=80
+
+python:
+  - "2.7"
+  - "3.4"
+  - "3.5"
+  - "3.6"
+
+script: coverage run --source=mmcv setup.py test
+
+after_success: codecov
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