Remove references to Travis CI

We do no longer use it.

.travis.yml

@@ -1,60 +0,0 @@
-language: java
-
-matrix:
-  allow_failures:
-    - os: linux # this is really about OSX, Ubuntu is just bonus
-  include:
-    - os: linux
-      sudo: required
-      language: android
-    - os: osx
-      osx_image: xcode9
-      env: ANDROID_SDK_ROOT=/usr/local/share/android-sdk
-      env: ANDROID_HOME=/usr/local/share/android-sdk
-
-# The PPA is needed to provide all the fdroidserver deps on Ubuntu 14.04 trusty
-addons:
-  apt:
-    sources:
-      - sourceline: 'ppa:guardianproject/fdroidserver'
-    packages:
-    - bash
-    - pylint
-    - python3-dev
-    - python3-libcloud
-    - python3-pil
-    - python3-pyasn1
-    - python3-pip
-    - python3-yaml
-    - rsync
-    - pep8
-    - libjpeg-dev
-    - zlib1g-dev
-    - fdroidserver
-    - npm
-
-install:
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
-      brew update > /dev/null;
-      brew install bash python3 libmagic;
-      brew cask reinstall java;
-      brew cask install android-sdk;
-      mkdir "$ANDROID_HOME/licenses";
-      echo -e "\n8933bad161af4178b1185d1a37fbf41ea5269c55" > "$ANDROID_HOME/licenses/android-sdk-license";
-      echo -e "\n84831b9409646a918e30573bab4c9c91346d8abd" > "$ANDROID_HOME/licenses/android-sdk-preview-license";
-      echo y | $ANDROID_HOME/tools/bin/sdkmanager "platform-tools";
-      echo y | $ANDROID_HOME/tools/bin/sdkmanager "build-tools;25.0.2";
-    else
-      sudo pip3 install django;
-    fi
-  - ./setup.sh
-  - sudo pip3 install -r requirements-dev.txt
-  - npm install --user
-
-script:
-  - ./tests/test-units.sh
-
-after_failure:
-  - cd $TRAVIS_BUILD_DIR
-  - ls -lRa env
-  - ls -lR | curl -F 'clbin=<-' https://clbin.com