Handle linux restart

[brablc]

When restart occurs the lazysar cannot handle output:

05:43:00 AM     all      0.02      0.00      0.06      0.00      0.47     99.45
Average:        all      0.05      0.00      0.09      0.01      0.87     98.98

05:44:52 AM  LINUX RESTART	(6 CPU)

05:50:11 AM     CPU     %user     %nice   %system   %iowait    %steal     %idle
05:51:35 AM     all      0.02      0.00      0.05      0.00      0.02     99.91