Create events table builder

[arjunsridhar12345]

Referencing https://github.com/AllenNeuralDynamics/aind-physio-arch/issues/1062, create a module to return the events table as a dataframe. Use the events defined in https://github.com/AllenNeuralDynamics/aind-physio-arch/issues/1072 as reference for building this.

For now, will store the sidecar.json as well so it is versioned in the repo.

[arjunsridhar12345]

On pause as working with HED tag team to iterate and validate.