Updates to ESLint

- Add .eslintignore file
- Add linting task to package.json
- Include linting task in Travis build

.eslintignore

@@ -0,0 +1,3 @@
+.eslintrc.js
+Gruntfile.js
+node_modules

.travis.yml

@@ -7,7 +7,8 @@ before_install:
 cache:
   npm: true
 script:
-- npm run deploy
+  - npm run lint
+  - npm run deploy
 if: tag IS present
 deploy:
   provider: releases

package.json

@@ -4,6 +4,7 @@
   "description": "A simple way to encrypt and decrypt your files",
   "main": "main.js",
   "scripts": {
+    "lint": "./node_modules/.bin/eslint **/*.js --fix",
     "build-grunt": "./node_modules/.bin/grunt build",
     "build-mac-x64": "./node_modules/.bin/electron-packager . --overwrite --platform=darwin --arch=x64 --icon=assets/icons/icon.icns --prune=true --out=release-builds",
     "zip-mac-x64": "zip -r release-builds/encrypt0r-mac.zip release-builds/encrypt0r-darwin-x64",