Add pid parameter to writeScratch
debug.h compile++
drop useless cast
wrap json.h in extern C
Merge pull request #13 from codius/misc-fixes

Misc fixes
Split out setup from exec
build node sandbox with rtti
Split out execv functionality into an ExecSandbox
Implement a thread-based sandbox for testing
Pass parameters to syscalls in testing
Split out common sandbox test code
consistent exit status on thread sandbox
use new debugging tools
Stop signal when sandbox is destroyed
remove useless vector
bare_pointers--
Make SandboxIPC destructor virtual
Properly read an empty string into a codius result
Implement VFS tests and a method to catch exceptions from sandboxed threads
Return Undefined if there is no json in a ipc response