Split up the utils package

[joshklop]

For example, we can have small network and log packages.

Two benefits:

• Clarity. Better to avoid ambiguous package names like common, utils, pkg, etc.
• Dependency management. A user may depend on a package that only uses utils/log and utils/network, but that user will have the full utils package compiled into the binary.

[joshklop]

Note: would like to avoid implementing this until @IronGauntlets (and anyone else who has an opinion) has a say.

[rianhughes]

I would also be in favour of this, and think it's also relevant for the final point in the refactoring PR
"Extract common types from the feeder package and rpc package to the utils package to reduce duplication."

[IronGauntlets]

@joshklop I am happy to split the utils package into multiple sub-packages. It might be better to have them as a separate package at the root level. I don't have a strong opinion on either one