Pipe layer traces to internal-proxy

[DmitryDodzin]

To prevent any unexpected behaviour with child processes that are spawned with unpiped stdout/stdin/stderr mirrord layer should never print to stdout but send everything to internal-proxy like mirrord-console and only print to console in mirrord-cli process

[t4lz]

I think this contradicts #1714 a bit. As a daemon the internal-proxy does not write to the running app's stderr.

[aviramha]

Maybe it's time we expose a HTTP interface from internal proxy that allows easier debugging :P