GitLab

Adds callbacks to manage connections, also removes network receiver methods from public graphsync
interface, and updates libp2p to handle go-libp2p-core refactor

Updates IPLD Bridge to use latest go-ipld-prime and runs and actual round trip test using GraphSync,
go-ipld-prime, and real selectors

Complete functionality to initialize response manager and process incoming requests

fix #7, fix #8

Creates the Response Manager that processes incoming requests, initiates selector traversal, and
generates responses