glideFactoryLogParser: In case of glideins not exiting properly, the log parser will set the duration as None rather than crashing.  This fixes a bug for preemption using SIGHUP at Purdue.
glideFactoryLogParser: In case of glideins not exiting properly, the log parser will set the duration as None rather than crashing.  This fixes a bug for preemption using SIGHUP at Purdue.

bbockelm/glideinWMS,bbockelm/glideinWMS,bbockelm/glideinWMS,bbockelm/glideinWMS