Tweak CI config files.

.appveyor.yml

@@ -0,0 +1,31 @@
+version: "{build}"
+
+clone_depth: 5
+
+environment:
+  RUBY_FOLDER_VERSION: "24-x64"
+  PLATFORM: "x64"
+
+install:
+  - SET "PATH=C:\Ruby%RUBY_FOLDER_VERSION%\bin;%PATH%"
+  - bundle install --retry 3 --jobs=%NUMBER_OF_PROCESSORS% --clean --path vendor\bundle
+  - ps: Install-Product node "10" $env:PLATFORM
+  - npm ci
+
+build: off
+
+test_script:
+  - ruby -v
+  - gem -v
+  - bundle -v
+  - node -v
+  - npm -v
+  - java -version
+  - npm test
+
+matrix:
+  fast_finish: true
+
+cache:
+  - '%APPDATA%\npm-cache\ -> .appveyor.yml,package.json,package-lock.json'
+  - 'vendor\bundle -> .appveyor.yml,Gemfile,Gemfile.lock'

.travis.yml

@@ -1,27 +1,31 @@
 sudo: required
 
-dist: trusty
+git:
+  depth: 5
 
 language: node_js
 
 node_js:
   - "10"
 
 env:
-  matrix:
+  global:
     - RUBY_VERSION=2.4
 
 before_install:
   - rvm use $RUBY_VERSION --install --binary --fuzzy
 
 install:
-  - npm install
+  - npm ci
   - bundle install --retry 3 --clean --path vendor/bundle
 
 matrix:
   fast_finish: true
 
 cache:
   directories:
-    - node_modules
+    - "$HOME/.npm"
     - vendor/bundle
+
+notifications:
+  email: false