use yarn on appveyor & autoinstall plugin deps

.travis.yml

@@ -14,8 +14,7 @@ cache:
     - app/node_modules
 
 before_install:
-    - yarn install
-    - scripts/install-deps.js
+    - yarn
 
 script:
     - scripts/build-native.js

appveyor.yml

@@ -7,18 +7,18 @@ environment:
   nodejs_version: "10"
 
 cache:
-  - '%USERPROFILE%\.electron'
+  - "%USERPROFILE%\\.electron"
+  - "%LOCALAPPDATA%\\Yarn"
 
 version: "{build}"
 
 install:
   - ps: Install-Product node $env:nodejs_version $env:platform
-  - npm install
-  - node scripts/install-deps.js
+  - yarn
   - node scripts/build-native.js
 
 build_script:
-  - npm run build
+  - yarn run build
   - node scripts/prepackage-plugins.js
   - node scripts/build-windows.js
 

package.json

@@ -126,7 +126,7 @@
     "start": "cross-env DEV=1 electron app --debug",
     "prod": "cross-env DEV=1 electron app",
     "lint": "tslint -c tslint.json -t stylish terminus-*/src/**/*.ts terminus-*/src/*.ts app/src/*.ts",
-    "postinstall": "install-app-deps"
+    "postinstall": "node ./scripts/install-deps.js"
   },
   "repository": "eugeny/terminus"
 }