I understand this is a recent update to MacOS but just wanted get this on the roadmap if it hasn't been tackled already. Thanks :)

## Environments
__OS:__  OSX
__Selenium Version:__  Selenium server standalone <= 3.14.0
__Browser:__  Any
__Browser Version:__ Any

## Expected Behavior
Selenium Grid hub routes webdriver traffic to specified `platform[Name]: macos 10.14` or `mojave`

## Actual Behavior
No current support for node platform target MacOS 10.14 Mojave.
Desired capabilities `platform[Name]` set to `macos 10.14` or `mojave` fails to find corresponding selenium node.
__Workaround:__
Disable all other MacOS platform nodes and target `platform[Name]: "MAC"`

## Steps to reproduce -
Create a selenium grid with OSX 10.12/13 and 10.14.
Run tests with desired capabilities `platform[Name]: "mojave"`.

## Reference
Known and Supported Platforms that WebDriver runs on: 
https://github.com/SeleniumHQ/selenium/blob/master/java/client/src/org/openqa/selenium/Platform.java
Doesn't include identifier for MacOSX 10.14 Mojave
@Override
    public Platform family() {
      return null;
    }
  },
  /**
   * For versions of Windows that "feel like" Windows XP. These are ones that store files in
   * "\Program Files\" and documents under "\\documents and settings\\username"
   */
  XP("Windows Server 2003", "xp", "windows", "winnt", "windows_nt", "windows nt") {
    @Override
    public Platform family() {
      return WINDOWS;
    }
  },
  /**
   * For versions of Windows that "feel like" Windows Vista.
   */
  VISTA("windows vista", "Windows Server 2008", "windows 7", "win7") {
    @Override
    public Platform family() {
      return WINDOWS;
    }
  },
  /**
   * For versions of Windows that "feel like" Windows 8.
   */
  WIN8("Windows Server 2012", "windows 8", "win8") {
    @Override
    public Platform family() {