From 0.1 to 0.1a
 - removed a silly bug that prevented the lockfiles for dumping not to
   be erased when the dump was empty. This left a lot of empty lockfiles
   in /tmp. Arghhhh.

From 0.1a to 0.2
 - removed a race condition in the signal handling (SIGCHLD).
   This was introduced when I added the dump process, so it is
   possible for both children to exit at the same time.
   This resulted in a zombie dump process on slow or heavy loaded
   machines.
 - Added pid file creation (/var/run/nacctd.pid a la crond) and
   detection. 
