Creating one xd-yarn shell script to replace the xd-install, xd-admin and xd-container ones

- Available command options are:

  - xd-yarn -p <PATH_TO_DIRECTORY_FOR_APP_ARTIFACTS> push

  - xd-yarn start admin

  - xd-yarn start container

- the push command creates a manifest.yml in the current directory or it can be directed to specific location using -f <PATH_TO_DIRECTORY_FOR_APP_ARTIFACTS>. Instead of -p we can use --path and instead of -f we can use --manifest.