This commit adds the skeleton for an issue transfer command.
Almost all of the functionality is implemented, but it is missing
the actual transfer of issues. I'm nervous about testing this, so
I'm going to implement the rest of the functionality first.
This contains the basic framework for our new `monorepo-merge`
command. The goal will be for this command to handle the heavy lifting
for merging repositories with full history. It will (ideally) bring any
plugin or package into the repository in a ready-to-use state.
Christopher Allford
RJChow