Use addons to define dependencies

.travis.yml

@@ -7,10 +7,25 @@ os:
 - linux
 env:
   - UPLOADTOOL_SUFFIX=$TRAVIS_BRANCH
+addons:
+  apt:
+    packages:
+      - libjpeg-dev
+      - libsndfile1-dev
+      - libsigc++-2.0-dev
+      - libfontconfig1-dev
+      - libxft-dev
+      - libcairo-dev
+      - python3-pip
+      - python3-setuptools
+      - python3-wheel
+      - liblo-dev
+      - libjack-dev
+      - libsamplerate0-dev
+      - ninja-build
 install:
 - echo $HOME
 - echo $PWD
-- sudo apt-get install libjpeg-dev libsndfile1-dev libsigc++-2.0-dev libfontconfig1-dev libxft-dev libcairo-dev python3-pip python3-setuptools python3-wheel liblo-dev libjack-dev libsamplerate0-dev ninja-build
 - if cd ntk; then git pull; else git clone git://git.tuxfamily.org/gitroot/non/fltk.git ntk && cd ntk; fi
 - sudo ./waf configure build install && cd ..
 - pip3 install meson