Output format for inference results

[peichins]

Output format should modified to be

1. Long format.

• This will be larger files but is more compatible with most situations where it will be used
• Long format makes most sense where there are score thresholds per class

2. Include end time

• currently we don't include end time because it's always 5 second duration, however it will make it easier for downstream processes to use if we add it here, rather than require modifications to the format to add the end time