GraphQL support via cli (#5697)

* Including GraphQL options in CLI - now it was auto-generated

* Improving the way that the headers are passed to the playground

* Including README notes about GraphQL

* Improving final text

README.md

@@ -356,6 +356,148 @@ Live queries are meant to be used in real-time reactive applications, where just
 
 Take a look at [Live Query Guide](https://docs.parseplatform.org/parse-server/guide/#live-queries), [Live Query Server Setup Guide](https://docs.parseplatform.org/parse-server/guide/#scalability) and [Live Query Protocol Specification](https://github.com/parse-community/parse-server/wiki/Parse-LiveQuery-Protocol-Specification). You can setup a standalone server or multiple instances for scalability (recommended).
 
+# GraphQL
+
+[GraphQL](https://graphql.org/), developed by Facebook, is an open-source data query and manipulation language for APIs. In addition to the traditional REST API, Parse Server automatically generates a GraphQL API based on your current application schema.
+
+## Running
+
+```
+$ npm install -g parse-server mongodb-runner
+$ mongodb-runner start
+$ parse-server --appId APPLICATION_ID --masterKey MASTER_KEY --databaseURI mongodb://localhost/test --mountGraphQL --mountPlayground
+```
+
+After starting the server, you can visit http://localhost:1337/playground in your browser to start playing with your GraphQL API.
+
+***Note:*** Do ***NOT*** use --mountPlayground option in production.
+
+## Checking the API health
+
+Run the following:
+
+```graphql
+query Health {
+  health
+}
+```
+
+You should receive the following response:
+
+```json
+{
+  "data": {
+    "health": true
+  }
+}
+```
+
+## Creating your first object
+
+Since your application does not have a schema yet, you can use the generic `create` mutation to create your first object. Run the following:
+
+```graphql
+mutation CreateObject {
+  objects {
+    create(className: "GameScore" fields: { score: 1337 playerName: "Sean Plott" cheatMode: false }) {
+      objectId
+      createdAt
+    }
+  }
+}
+```
+
+You should receive a response similar to this:
+
+```json
+{
+  "data": {
+    "objects": {
+      "create": {
+        "objectId": "7jfBmbGgyF",
+        "createdAt": "2019-06-20T23:50:50.825Z"
+      }
+    }
+  }
+}
+```
+
+## Using automatically generated operations
+
+Parse Server learned from the first object that you created and now you have the `GameScore` class in your schema. You can now start using the automatically generated operations!
+
+Run the following to create a second object:
+
+```graphql
+mutation CreateGameScore {
+  objects {
+    createGameScore(fields: { score: 2558 playerName: "Luke Skywalker" cheatMode: false }) {
+      objectId
+      createdAt
+    }
+  }
+}
+```
+
+You should receive a response similar to this:
+
+```json
+{
+  "data": {
+    "objects": {
+      "createGameScore": {
+        "objectId": "gySYolb2CL",
+        "createdAt": "2019-06-20T23:56:37.114Z"
+      }
+    }
+  }
+}
+```
+
+You can also run a query to this new class:
+
+```graphql
+query FindGameScore {
+  objects {
+    findGameScore {
+      results {
+        playerName
+        score
+      }
+    }
+  }
+}
+```
+
+You should receive a response similar to this:
+
+```json
+{
+  "data": {
+    "objects": {
+      "findGameScore": {
+        "results": [
+          {
+            "playerName": "Sean Plott",
+            "score": 1337
+          },
+          {
+            "playerName": "Luke Skywalker",
+            "score": 2558
+          }
+        ]
+      }
+    }
+  }
+}
+```
+
+## Learning more
+
+Please look at the right side of your GraphQL Playground. You will see the `DOCS` and `SCHEMA` menus. They are automatically generated by analysing your application schema. Please refer to them and learn more about everything that you can do with your Parse GraphQL API.
+
+Additionally, the [GraphQL Learn Section](https://graphql.org/learn/) is a very good source to start learning about the power of the GraphQL language.
+
 # Upgrading to 3.0.0
 
 Starting 3.0.0, parse-server uses the JS SDK version 2.0.