misc.spawn node 0.8 compatibility: stdio data may come after exit.

Node 0.8 introduces the close event on the child_process to easily
handle this, but stdio close events are used for older node versions.
Use camel case naming.
Merge pull request #41 from dylanahsmith/handle-stdio-after-exit

misc.spawn node 0.8 compatibility: stdio data may come after exit.
find oldest successful build instead of just finding the oldest
Merge pull request #45 from racker/find_oldest_successful_build

find oldest successful build instead of just finding the oldest