Ensure that root logger is set up first
Update path to visualization tools
Turn off RPC serialization assertions by default
Document which methods are invoked in child process, and which are invoked in
parent
Fix major bug where runtime stats weren't passed back to parent properly.

Bug was introduced when we moved to a fork() replay model. It assumed shared
state, which totally fucked things up. We are now very explicit about what
runtime stats we pass back via RPC.