Updating readme with package.json instructions and callbackURL

Author: suryart

README.md

@@ -4,6 +4,7 @@
     - [Configuring your tests](#configuring-your-tests)
     - [Running the tests](#running-the-tests)
     - [Getting build information](#getting-build-information)
+    - [Stopping a running build](#stopping-a-running-build)
     - [Limitations](#limitations)
 - [Accessing test results](#accessing-test-results)
 - [License](#license)
@@ -78,10 +79,12 @@ The following table provides a reference for all the options that can be provide
 | `versions`        | A list of browser versions that you want to run your tests on. <br/><br/> **Example:** To run on versions 69, 67 and 65 provide `["69", "67", "65"]`                                                                              | Right now edge 80 and all chrome versions from 66 to 78 are supported |
 | `specs` <br/> (_deprecated_)           | This param is deprecated in favour of a more complete `cypress_proj_dir` param. The path to the spec files that need to be run on BrowserStack                                                                              | Takes a list of strings that point to location of the spec files                                                              |
 | `cypress_proj_dir`           | Path to the folder which contains `cypress.json` file. This path will be considered as the root path of the project.                                                                           |-                                                               |
+| `package_json_path`           | Absolute path to the `package.json` file of your application which uses cypress in its development dependency. This is used for resolving development dependecies before running the tests.  |-                                                               |
 | `project`         | Name of your project. This will be displayed in your Automate dashboard, and you'll be able to search & filter your tests based on the project name.                                                                                                                         | A string providing the name of the project                                                                                    |
 | `customBuildName` | Helps in providing a custom name for the build. This will be displayed in your Automate dashboard, and you'll be able to search & filter your tests based on the build name.                                                                                              | A string providing the name of the build                                                                                      |
 | `local`           | Helps in testing websites that cannot be accessed in public network. If you set this to `true`, please download the Local binary and establish a local connection first (you can learn how to do so [here](https://www.browserstack.com/local-testing/automate#command-line))                                                                       | Boolean: `true` / `false`. Set this to `true` if you need to test a local website. Set this to `false` if the website is accessible publicly.              |
 | `localIdentifier`           |  The BrowserStack Local tunnel that should be used to resolve requests. This is applicable only when you start a Local binary with a local identifier. Your tests might fail if you use an invalid local identifier. This option will be ignored if `local` option is set to `false`.                                                                       | A string if a tunnel identified by the Local identifier should be used (should be same as the one used to start the Local binary). Set this to `null` (default value) to resolve requests using Local without a Local identifier.              |
+| `callbackURL`           |  A callback URL which can be used as a hook to update your server about the build's status. A POST request will be made to this URL with tests data and their status in its body once the tests are completed.                                                                        | A string which is a valid URI. The endpoint must accept the POST method.             |
 
 ### Running the tests
 You can start running your test build using the following command.
@@ -212,7 +215,7 @@ Output:
 
 - `exec` and `task` are not allowed.
 - While using local, please make sure to create `/etc/hosts` entry pointing to some URL, and use that URL in the tests. The `localhost` URI doesn't work at the moment.
-- Installing custom npm packages are not supported at this moment.
+- Installing custom npm packages are not supported on Mac OS X at this moment.
 
 # Accessing test results