Adding Timestamp to sensor_msgs/Image and Parameters

[larsll]

Issue Number (if available): N/A

Description of changes:

• Populating the message header with a timestamp and unique identifier to allow for more accurate video production downstream.
• Add a parameter to define the rescaling factor
• Add a parameter to limit the number of frames per second to be produced
• Add a parameter to turn off the display stream
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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[pratik-nichat]

Hello @larsll,
Thank you for your interest in the AWS DeepRacer open-source initiative. I went through your commits and have a few comments regarding couple of them.

1. This commit should not be present since its already a part of the main branch currently, so if you could rebase your changes and remove this local commit, it would be cleaner.
2. Regarding this commit: The resizing has been originally set as default to 160x120 size image since this is the size that is expected by the neural network for inference as part of the AWS DeepRacer Core application. Hence suggestion is to keep a parameter to support this for the AWS DeepRacer core application specifically. I will leave it upto you to decide how to design that along with resizing wrt other scales.
   Thanks,
   Pratik

[larsll]

@pratik-nichat - After some motivating racing on Summit Berlin I have gone back and updated this Pull request. It should be backwards compatible.