Implement a copy command for configs

[jcfitzpatrick12]

Description

Currently, if a user wants to experiment with an existing config, such as by tweaking a single value, they must create a new one from scratch and then manually update each of its parameters.

We should create a new convenience command along the spirit of spectre create copy --tag <tag> --new-tag <new-tag>, which would create an identical config (same receiver, same operating mode, same parameters) under the new tag. As a sketch of the implementation, the new CLI function would:

• Read the existing config, and extract the receiver, mode and parameters (like here)
• Then make a new config (like here)