Replace common package with pkg

[lumtis]

Describe the Issue
common package is a bit too general as a name and group too many different thing under the same namespace. Also it is generally not recommended to use common as a name

Expected Outcome
Idea of the issue is to group the different logic in common into reusable and scoped packages under pkg

pkg/chains
pkg/address
pkg/proofs

as conventional in GO https://pkg.go.dev/github.com/geektime007/mgmt/pkg#section-readme