Add confirmation message to syscall_test
Make async syscalls look like Akaros events
Fill in stack properly for the main thread
Fix up the autotool stuff

Originally this was copied form lithe, so there were some unnecessary
things in there.
Fix spacing and remove printf_safe() (not needed)
Error out on upthread_sigmask or upthread_kill
We should only incrementally ask for 1 vcore

The old way would sometimes result in us asking for too few if
threads_ready spiked up quickly beyond the number of vcores we could ask
for (without requesting some we could still get...).
Fork to create upthread with per vcore run queues
Remove the active queue

Not really needed, and will hinder our performance once we go to per-vcore run
queues in the subsequent commits.
Change the name to pvcq for per vcore queue
Working version with global ready queue

It works, but its slow on inserts.  It appears that even with the wait free
list, there is lots of contention on inserts into the list, causing things to
run slowly.
Make the wfls per vcore too.

This speeds things up ALOT, but we still dont' get nearly as many context
switches per second as native linux, and I'm not sure why.
Revert back to a simpler, version :/

This dead simple version is the highest performant one.  There is no stealing
element to it, but that appears to actually be a good thing since it
simplifies the critical path.
Quick optimization for yielding
Cache align the thread queue.

This doesn't seem to help as much as I'd hoped it would.  I'm next going to
try and remove all contention on the 'new thread' queue.
Cache align stuff that matters
Macroize access to the pvc data
I was cache aligning my structs, but not my mallocs
Add ability to steal work when pvc queue empty.
Add hooks to set num_vcores and turn on ss optimization