Avoid chaincode packages picking up dependencies on later v2.x releases,
such as v2.5.x. Later releases may exploit features not compatible with
the v2.2 chaincode container runtime.
Signed-off-by: Mark S. Lewis <Mark.S.Lewis@outlook.com>
Update ERC-20 readme to indicate the new contract name
and add TransferFrom tutorial for Go chaincode.
Signed-off-by: David Enyeart <enyeart@us.ibm.com>