Handles parsing either v1 or v2 of the proxy protocol

Handles the plain text version of the proxy protocol as defined in section 2.1: https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt

Handles the binary version of the proxy protocol as defined in section 2.2: https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt