Cleanup undelivered messages on shutdown
Fix busywait on OSX

Signed-off-by: Sean Ogden <positivelyskewed.sf@gmail.com>
correct signal behavior on OSX

Signed-off-by: Sean Ogden <positivelyskewed.sf@gmail.com>
Add tools for checking contention
Merge branch 'fix_osx_signals' of git://github.com/seanogden/busybee

* 'fix_osx_signals' of git://github.com/seanogden/busybee:
  correct signal behavior on OSX
  Fix busywait on OSX

Conflicts:
	busybee.cc