optional_requirements.txt added in travis script
This commit adds command to install
`optional-requirements.txt` file in `.travis.yml` file.
@@ -27,6 +27,7 @@ before_install:
- pip3 install --upgrade pip
- pip3 install -r requirements.txt
- pip3 install -r tests/requirements.txt
+ - pip3 install -r optional-requirements.txt
# command to run tests
script:
