This standardizes our method of running a payload: run a shared object with
argc/argv.  No special treatment for the jvm.

It expects penv to point to something.

Longer term it should be nice not to allocate the bars at all

This way, the payload may use the pthread APIs in the thread it started in.

Needed for pthread_attr_*() (and in general to make sure the stack is
a regular vma as expected by the payload).

segfaults.

Create a central place the managed the console driver (just isa-serial for
now), and exposes them as a device file and to the debug output routines.

Destroy the drivers on OS reset (currently just call it from the loader directly) It fixes the issue of gdb breakage w/ the drivers

There now is a public add_object and a private set_object method, which
describe the two totally different actions much better.

Style requires manual edititing of loader.cc to run, no automated way
to pick up whole directories in the manifest, and we won't clear the
environment before running the next .so

This makes the apic immediately usable.

This seems to break the actual jvm execution for some reason.

Various changes to fit into the OSv environment.  This also includes
a ramfs in-memory full filesystem.  Bootfs is rewritten as a simple
unpacker into ramfs, and the fs class is modified to wrap the VFS
instead of being an abstract subclass.

Mirror the jre file layout closely, otherwise it gets confused.

Add a new hello_world test payload that can be used to test OSv functionality
more fine grained.  For now the binary loaded remains hardcoded in loader.cc
and still defaults to libjvm.so.

Change the directory structure a little to conform with jvm expecations
(removing server/ from libjvm.so).

dlopen() uses files, so do so as well.  Change DT_NEEDED handling to add the
path.

This way everyone's running on a similar sized stack.  Theoretically the
main thread can be destroyed as well.

the PIC will spew some spurious interrupts which we don't want.

Eventually loader dump them into the console for debug