Use top-level matrix idiom (crossbario#485)

* use top-level matrix idiom

* empty commit

.travis.yml

@@ -1,29 +1,29 @@
-language: android
-android:
-  components:
-    - tools
-    - platform-tools
-    - tools
-    - build-tools-29.0.2
-    - android-29
-  licenses:
-    - 'android-sdk-preview-license-.+'
-    - 'android-sdk-license-.+'
-    - 'google-gdk-license-.+'
-
-services:
-  - docker
-
-install:
-  - if [[ $(git diff --name-only $TRAVIS_COMMIT_RANGE) =~ "docker/Dockerfile.netty" ]]; then docker build -t crossbario/autobahn-java:netty -f ./docker/Dockerfile.netty .; fi
-
-before_script:
-  - docker run -d -p 8080:8080 --name crossbar crossbario/crossbar
-  - docker run -d --link crossbar -v ${PWD}/demo-gallery/python:/test crossbario/autobahn-python python -u /test/test_component2.py
-
-script:
-  - ./gradlew :autobahn:build connectedCheck
-  - docker run --rm -it --link crossbar -v ${PWD}:/workspace crossbario/autobahn-java:netty /bin/bash -c "gradle installDist -PbuildPlatform=netty && /workspace/demo-gallery/build/install/demo-gallery/bin/demo-gallery ws://crossbar:8080/ws"
+matrix:
+  include:
+    - language: android
+      android:
+        components:
+          - tools
+          - platform-tools
+          - tools
+          - build-tools-29.0.2
+          - android-29
+        licenses:
+          - 'android-sdk-preview-license-.+'
+          - 'android-sdk-license-.+'
+          - 'google-gdk-license-.+'
+      script:
+        - ./gradlew :autobahn:build connectedCheck
+    - language: minimal
+      services:
+        - docker
+      install:
+        - if [[ $(git diff --name-only $TRAVIS_COMMIT_RANGE) =~ "docker/Dockerfile.netty" ]]; then docker build -t crossbario/autobahn-java:netty -f ./docker/Dockerfile.netty .; fi
+      before_script:
+        - docker run -d -p 8080:8080 --name crossbar crossbario/crossbar
+        - docker run -d --link crossbar -v ${PWD}/demo-gallery/python:/test crossbario/autobahn-python python -u /test/test_component2.py
+      script:
+        - docker run --rm -it --link crossbar -v ${PWD}:/workspace crossbario/autobahn-java:netty /bin/bash -c "gradle installDist -PbuildPlatform=netty && /workspace/demo-gallery/build/install/demo-gallery/bin/demo-gallery ws://crossbar:8080/ws"
 
 deploy:
   provider: releases