fix: update to app instead of core

Author: KaneFreeman

README.md

@@ -12,7 +12,7 @@ site](https://staticjscms.netlify.app).
 ## Install
 
 ```shell
-npm install @staticcms/core gatsby-plugin-static-cms
+npm install @staticcms/app gatsby-plugin-static-cms
 ```
 
 ## How to use
@@ -65,11 +65,11 @@ The js module might look like this:
 
 ```javascript
 /**
- * The default export of `@staticcms/core` is an object with all of the Static CMS
+ * The default export of `@staticcms/app` is an object with all of the Static CMS
  * extension registration methods, such as `registerWidget` and
  * `registerPreviewTemplate`.
  */
-import CMS from "@staticcms/core"
+import CMS from "@staticcms/app"
 
 /**
  * Any imported styles should be automatically be applied to the editor preview
@@ -118,7 +118,7 @@ plugins: [
 The js module might look like this:
 
 ```javascript
-import CMS from "@staticcms/core"
+import CMS from "@staticcms/app"
 
 /**
  * Optionally pass in a config object. This object will be merged into `config.yml` if it exists

src/cms.js

@@ -1,4 +1,4 @@
-import CMS from "@staticcms/core"
+import CMS from "@staticcms/app"
 // set global variables required by Gatsby's components
 // https://github.com/gatsbyjs/gatsby/blob/deb41cdfefbefe0c170b5dd7c10a19ba2b338f6e/docs/docs/production-app.md#window-variables
 // some Gatsby components require these global variables set here:

src/gatsby-node.js

@@ -101,10 +101,10 @@ exports.onCreateWebpackConfig = (
       assetName: `react-dom.production.min.js`,
     },
     {
-      name: `@staticcms/core`,
-      global: `StaticCmsCore`,
+      name: `@staticcms/app`,
+      global: `StaticCmsApp`,
       assetDir: `dist`,
-      assetName: `static-cms-core.js`
+      assetName: `static-cms-app.js`
     },
   ]