chore(travis): cleanup the tests on Travis.

Remove OSX tests for Node 4, remove tests for Node 5. Other cleanup tasks.

Author: hansl

.travis.yml

@@ -1,31 +1,25 @@
 dist: trusty
 sudo: required
+
 language: node_js
-node_js:
-  - "4"
-os:
-  - linux
+
 env:
   global:
     - DBUS_SESSION_BUS_ADDRESS=/dev/null
-  matrix:
-    - SCRIPT=lint
-    - SCRIPT=build
-    - SCRIPT=test
-    - NODE_SCRIPT=tests/e2e_runner.js
-    - NODE_SCRIPT="tests/e2e_runner.js --nightly"
-#    - TARGET=mobile SCRIPT=mobile_test
+
 matrix:
   fast_finish: true
   allow_failures:
-    - node_js: "5"
     - os: osx
     - env: NODE_SCRIPT="tests/e2e_runner.js --nightly"
   include:
-    - node_js: "5"
+    - node_js: "6"
       os: linux
-      env: SCRIPT=test
-    - node_js: "5"
+      env: SCRIPT=lint
+    - node_js: "6"
+      os: linux
+      env: SCRIPT=build
+    - node_js: "4"
       os: linux
       env: NODE_SCRIPT=tests/e2e_runner.js
     - node_js: "6"
@@ -34,17 +28,19 @@ matrix:
     - node_js: "6"
       os: linux
       env: NODE_SCRIPT=tests/e2e_runner.js
-    - node_js: "4"
-      os: osx
-      env: SCRIPT=test
-    - node_js: "4"
+    - node_js: "6"
       os: osx
       env: NODE_SCRIPT=tests/e2e_runner.js
+
+    # Optional builds.
     - node_js: "6"
       os: osx
       env: SCRIPT=test
     - node_js: "6"
-      os: osx
+      os: linux
+      env: NODE_SCRIPT="tests/e2e_runner.js --nightly"
+    - node_js: "7"
+      os: linux
       env: NODE_SCRIPT=tests/e2e_runner.js
 
 before_install: