build_parameters_recorders is inefficient

[knoxsp]

With the new approach of storing all parameters and recorders as global network variables, we now have a situation where downloading and setting these up is becoming very slow for bigger networks.

Can we:

1. Identify the cause of the slowdown in this function?
2. Find any hydra-base functions which might help such as downloading data in batches
3. If no such functions exist, create an issue for either implementing these functions or improving this functionality in hydra-base