Allow alternate video sources

[sberan]

Description

This PR adds a VideoFrameProducer class which can be passed as a video source. This allows us to work with video sources that cv2 doesn't support such as basler.

Here is an example script which creates a VideoFrameProducer for a camera which isn't supported by opencv.

@PawelPeczek-Roboflow what do you think of this abstraction? Is there a better way we could be doing this? Should we rename the interface? If you like the abstraction, I will clean it up and add docs and tests.

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

How has this change been tested, please provide a testcase or example of how you tested the change?

tested locally

Any specific deployment considerations

n/a

Docs

• TODO. the docs will need to be updated