- Conform to standard Python C coding styles.

- All static symbols were renamed and shorted.

- Eyeballed all return values and memory references.

- Fixed a bug in signal.pause() so that exceptions raised in signal
  handlers are now properly caught after pause() returns.

- Removed SIGCPU and SIGFSZ.  We surmise that these were typos for the
  previously missing SIGXCPU and SIGXFSZ.