Added PercentageBarAnnotator Class

[xaristeidou]

Description

Added PercentageBoxAnnotator annotation, which shows the confidence level of the predictions

List any dependencies that are required for this change.

Type of change

Please delete options that are not relevant.

• [x] New feature (non-breaking change which adds functionality)
• [x] This change requires a documentation update

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

Predicted with YOLOv8 and plotted annotation with PercentageBarAnnotator annotation class and Detections class (for detections results).

Any specific deployment considerations

Additional feature

Docs

• [ ] Docs updated? What were the changes: Just added Class and function descriptions

Further improvement

• [x] Have to add functionality for position selection