Use pip3 in Makefile.

.travis.yml

@@ -17,7 +17,7 @@ before_install:
  - "sh -e /etc/init.d/xvfb start"
 
 install:
-  - sudo pip3 install . 
+  - sudo make install
 
 before_script:
   - export PYTHONPATH=`pwd`:$PYTHONPATH

Makefile

@@ -23,7 +23,7 @@ input: 	clean install docs
 
 install:
 	@echo "*** Installing PyQSO"
-	python3 setup.py install
+	pip3 install .
 
 docs:
 	@echo "*** Building the documentation"