Remove '@types/node' and '@types/graphql' from dependencies (#535)

Inspired by: https://github.com/stream-utils/raw-body/blob/master/README.md#typescript

Author: IvanGoncharov

README.md

@@ -12,6 +12,16 @@ Create a GraphQL HTTP server with any HTTP web framework that supports connect s
 npm install --save express-graphql
 ```
 
+### TypeScript
+
+This module includes a [TypeScript](https://www.typescriptlang.org/)
+declaration file to enable auto complete in compatible editors and type
+information for TypeScript projects. This module depends on 'graphql' and the Node.js
+types, so install `@types/graphql` and `@types/node`:
+
+```sh
+$ npm install --save --dev @types/graphql @types/node
+```
 
 ## Simple Setup
 

package.json

@@ -49,8 +49,6 @@
  "start": "node -r @babel/register examples/index.js"
  },
  "dependencies": {
- "@types/graphql": "*",
- "@types/node": "*",
  "accepts": "^1.3.7",
  "content-type": "^1.0.4",
  "http-errors": "^1.7.3",

yarn.lock

@@ -241,16 +241,6 @@
  resolved "https://registry.yarnpkg.com/@sinonjs/text-encoding/-/text-encoding-0.7.1.tgz#8da5c6530915653f3a1f38fd5f101d8c3f8079c5"
  integrity sha512-+iTbntw2IZPb/anVDbypzfQa+ay64MW0Zo8aJ8gZPWMMK6/OubMVb6lUPMagqjOPnmtauXnFCACVl3O7ogjeqQ==
 
-"@types/graphql@*":
- version "14.2.2"
- resolved "https://registry.yarnpkg.com/@types/graphql/-/graphql-14.2.2.tgz#10f197e6f8559c11b16d630c5e9c10c3c8e61c5e"
- integrity sha512-okXbUmdZFMO3AYBEJCcpJFPFDkKmIiZZBqWD5TmPtAv+GHfjD2qLZEI0PvZ8IWMU4ozoK2HV2lDxWjw4LbVlnw==
-
-"@types/node@*":
- version "12.0.12"
- resolved "https://registry.yarnpkg.com/@types/node/-/node-12.0.12.tgz#cc791b402360db1eaf7176479072f91ee6c6c7ca"
- integrity sha512-Uy0PN4R5vgBUXFoJrKryf5aTk3kJ8Rv3PdlHjl6UaX+Cqp1QE0yPQ68MPXGrZOfG7gZVNDIJZYyot0B9ubXUrQ==
-
 "@types/parsimmon@^1.3.0":
  version "1.10.0"
  resolved "https://registry.yarnpkg.com/@types/parsimmon/-/parsimmon-1.10.0.tgz#ffb81cb023ff435a41d4710a29ab23c561dc9fdf"