Add support for proxy protocol headers in network policies

[warroyo]

Describe the problem/challenge you have

When using proxy protocol to get the source IP of a client I am unable to write a network policy that uses that client IP from the proxy protocol headers.

Describe the solution you'd like

I would like to be able to create a network policy or cluster network policy that can get the source ip from the proxy protocol headers and then it can be used to allow/deny traffic.