feat: add a README

Author: felipelube

README.md

@@ -0,0 +1,16 @@
+# NPM Script Webhook
+Tiny web app for executing a npm task after a successful token authentication request.
+
+The request need to be sent via POST in the following format:
+```json
+{
+  "secret": "51999777-c86a-41c0-b69f-2e3f9ccc0f3b"
+}
+```
+
+## Configuration
+The following ENV vars are used to configure the app:
+- NSW_TOKEN: (required) the token used to authenticate a request
+- NSW_WORK_DIR: the working dir with the npm script, defaults to `/var/www/html`
+- NSW_SCRIPT_NAME: the name of the task, defaults to `build`
+- NSW_TIMEOUT: the maximum time to wait (in ms) for the task to complete, defaults to 30 seconds