Cleaned up some of the superfluous variations of onServer*()/onClient*() in the debugger commands. The separation was a leftover of the days when we had the VM and the compiler. The entire DebuggerCommand interface, what's public/protected/private, etc. could use a serious cleanup, but I'm not going that far now. I mostly wanted to clean this up to make some other work we need to do server-side less complicated.
This change is mostly for FB internal organizational reasons.
Building is not effected beyond the fact that the target now
lands in hphp/hhvm/hhvm rather than src/hhvm/hhvm.
Mike Magruder