Fix .travis.yml formatting, was not installing apt packages

.travis.yml

@@ -6,22 +6,22 @@ node_js:
 - '6.9'
 
 addons:
-  artifacts: true
-  apt:
-    sources:
-    - ubuntu-toolchain-r-test
-    packages:
-    - build-essential
-    - clang
-    - fakeroot
-    - g++-4.8
-    - git
-    - libgnome-keyring-dev
-    - xvfb
-    - rpm
-    - libxext-dev
-    - libxtst-dev
-    - libxkbfile-dev
+- artifacts: true
+- apt:
+  sources:
+  - ubuntu-toolchain-r-test
+  packages:
+  - build-essential
+  - clang
+  - fakeroot
+  - g++-4.8
+  - git
+  - libgnome-keyring-dev
+  - xvfb
+  - rpm
+  - libxext-dev
+  - libxtst-dev
+  - libxkbfile-dev
 
 branches:
   only:

scripts/postinstall.js

@@ -37,12 +37,13 @@ function npm(cmd, options) {
 // For speed, we cache app/node_modules. However, we need to
 // be sure to do a full rebuild of native node modules when the
 // Electron version changes. To do this we check a marker file.
-const cacheVersionPath = './app/node_modules/.postinstall-target-version';
+const appModulesPath = path.resolve(__dirname, '..', 'app', 'node_modules');
+const cacheVersionPath = path.join(appModulesPath, '.postinstall-target-version');
 const cacheElectronTarget = fs.existsSync(cacheVersionPath) && fs.readFileSync(cacheVersionPath).toString();
 
 if (cacheElectronTarget !== npmElectronTarget) {
   console.log(`\n-- Clearing app/node_modules --`)
-  rimraf.sync(path.resolve(__dirname, '..', 'app', 'node_modules'));
+  rimraf.sync(appModulesPath);
 }
 
 // run `npm install` in ./app with Electron NPM config