Update Docs for Nuxt

Author: alvarosabu

.npmignore

@@ -10,6 +10,7 @@ postcss.config.js
 .prettierrc
 .git
 **/.git/
+**/node_modules/
 yarn.lock
 /dev
 /docs

dev/nuxt/nuxt.config.js

@@ -52,7 +52,7 @@ export default {
    */
   modules: [['@asigloo/vue-dynamic-forms/nuxt']],
   dynamicForms: {
-    theme: 'materialize',
+    theme: 'default',
   },
   /*
    ** Build configuration

docs/guide/install.md

@@ -36,3 +36,39 @@ export {
     ...
 }
 ```
+
+### Install it as Nuxt.js Module
+
+Vue Dynamic Forms provides a [Nuxt.js](https://nuxtjs.org/) module for easily importing the library into your Nuxt.js App.
+
+Nuxt.js version `2.12.2` (or greater) is recommended.
+
+#### Getting dependencies
+
+```bash
+yarn add @asigloo/vue-dynamic-forms
+
+# or, using NPM
+npm install @asigloo/vue-dynamic-forms
+```
+
+Add `@asigloo/vue-dynamic-forms/nuxt` to modules section of your `nuxt.config.js` file.
+
+```javascript
+module.exports = {
+  modules: ['@asigloo/vue-dynamic-forms/nuxt'],
+};
+```
+
+#### Choosing theme
+
+You can select directly the theme trough `dynamicForms` options like this
+
+```javascript
+module.exports = {
+  modules: ['@asigloo/vue-dynamic-forms/nuxt'],
+  dynamicForms: {
+    theme: 'materialize',
+  },
+};
+```

nuxt/index.js

@@ -5,19 +5,18 @@ const THEMES = ['default'];
 module.exports = function nuxtDynamicForms(moduleOptions) {
   const options = Object.assign({}, this.options.dynamicForms, moduleOptions);
 
-  if (THEMES.includes(options.theme)) {
-    this.options.css.push(
-      `@asigloo/vue-dynamic-forms/src/styles/themes/${options.theme}.scss`,
-    );
-  } else {
-    this.options.css.push(
-      `@asigloo/vue-dynamic-forms/src/styles/themes/default.scss`,
-    );
-    console.warn(
-      `[vue-dynamic-forms warn]: Theme '${options.theme}' does not exit yet. \n` +
-        `Selecting theme 'default'. \n` +
-        `You can propose it as a new theme by creating a PR here 'https://github.com/alvarosaburido/vue-dynamic-forms/pulls'`,
-    );
+  if (options && options.theme !== undefined) {
+    if (THEMES.includes(options.theme)) {
+      this.options.css.push(
+        `@asigloo/vue-dynamic-forms/src/styles/themes/${options.theme}.scss`,
+      );
+    } else {
+      console.warn(
+        `[vue-dynamic-forms warn]: Theme '${options.theme}' does not exit yet. \n` +
+          `Selecting theme 'default'. \n` +
+          `You can propose it as a new theme by creating a PR here 'https://github.com/alvarosaburido/vue-dynamic-forms/pulls'`,
+      );
+    }
   }
   // Register plugin
   this.addPlugin({