add libusb for travis

diff --git a/.travis.yml b/.travis.yml
index 58f60ffa7cd2eaf6e56128c2ae151823d9a4d3ea..7aa1ca96b54aa91ac32d57771e581be6797e7d39 100755 (executable)
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,6 +19,7 @@ install:
   - pip install -r requirements.txt
   - pip install --force-reinstall pylint==1.9.2
   - pip install circuitpython-build-tools Sphinx sphinx-rtd-theme
   - pip install -r requirements.txt
   - pip install --force-reinstall pylint==1.9.2
   - pip install circuitpython-build-tools Sphinx sphinx-rtd-theme

+  - sudo apt-get install libusb-1.0

 
 script:
   - pylint src/**/*.py
 
 script:
   - pylint src/**/*.py