Support remote L7 traffic management

[hzxuzhonghu]

What would you like to be added:

As discussed, in kmesh we would want to implement a proxy(maybe call waypoint) which should be able to do L7 traffic management, telemetry and security enforcement. It can be deployed on any node of k8s or outside of the kubernetes cluster.

The waypoint can be for a single service， a namespace or even shared.

Why is this needed:

Currently kmesh L7 depends on kernel enhancement, which is coupled with OS version, and it cannot handle HTTPS HTTP2 and grpc protocol well. So we need a userspace proxy.

[hzxuzhonghu]

/assign @YaoZengzeng

[hzxuzhonghu]

cc @nlgwcy

[hzxuzhonghu]

done