[eslint-config-kibana] Add jest plugin and settings

This extracts the ui-specific eslint settings from elastic/kibana so they can
be applied to other repositories as well.

packages/eslint-config-kibana/.eslintrc.js

@@ -5,7 +5,7 @@ module.exports = {
     'mocha',
     'babel',
     'react',
-    'import'
+    'import',
   ],
 
   env: {
@@ -106,4 +106,4 @@ module.exports = {
     'import/no-named-as-default-member': 'error',
     'import/no-duplicates': 'error',
   }
-}
+}

packages/eslint-config-kibana/README.md

@@ -1,3 +1,31 @@
 # eslint-config-kibana
 
 The eslint config used by the kibana team
+
+## Usage
+
+To use this eslint config, just install the peer dependencies and reference it 
+in your `.eslintrc`:
+
+```javascript
+{
+  extends: [
+    '@elastic/eslint-config-kibana'
+  ]
+}
+```
+
+## Optional jest config
+
+If the project uses the [jest test runner](https://facebook.github.io/jest/), 
+the `@elastic/eslint-config-kibana/jest` config can be extended as well to use 
+`eslint-plugin-jest` and add settings specific to it:
+
+```javascript
+{
+  extends: [
+    '@elastic/eslint-config-kibana',
+    '@elastic/eslint-config-kibana/jest'
+  ]
+}
+```

packages/eslint-config-kibana/jest.js

@@ -0,0 +1,15 @@
+module.exports = {
+  plugins: [
+    'jest',
+  ],
+
+  env: {
+    'jest/globals': true,
+  },
+
+  rules: {
+    'jest/no-disabled-tests': 'error',
+    'jest/no-focused-tests': 'error',
+    'jest/no-identical-title': 'error',
+  }
+}

packages/eslint-config-kibana/package.json

@@ -22,6 +22,7 @@
     "eslint": "^4.1.0",
     "eslint-plugin-babel": "^4.1.1",
     "eslint-plugin-import": "^2.6.0",
+    "eslint-plugin-jest": "^20.0.3",
     "eslint-plugin-mocha": "^4.9.0",
     "eslint-plugin-react": "^7.0.1"
   }