Add /proc/interrupts parsing support
Parse ethtool -i
A first stab at parsing sosreports and including info in the pdf

If the sar file pointed at is part of an sosreport, /proc/interrupts
will be parsed and the devices triggering the interrupt will be
mentioned in the graph
Fix the --labelsfile switch as it was broken after the maxgraphs changes
Add more complex pdf example
Implemented /proc/interrupts parsing, clean up TODO
Implement display of reboot times in graphs

If the sarfile is part of an sosreport, /var/log/messages* will be
parsed and reboot times will be noted and displayed in the graphs.

As the parsing of the correct dates in /var/log/messages is quite
fragile, this feature is off by default. Set SHOW_REBOOTS = True
in SAR.py to use it.
Updated TODO
Added --showreboots option to show reboots in the graphs when part of an sosreport
Do not recurse subdirectories when parsing a whole /var/log/sa dir
Error out nicely when a directory contains no sar files
Fix txbyt/s description
Add new TODO item
Commit initial implementation of --custom switch

This switch allows to add graphs composed of arbitrary datasets to the pdf.
So --custom 'foo:udpsck,rawsck,tcp-tw' will add an additional page with
those three datasets graphed on a single page.
Make setup.py quiet by default
Currently workaround the issue of custom graphs and THREADED = True
Extend --list to print also start and end times of the sar intervals
Remove implemented TODO (--custom)
A couple of help usage clarifications
Fix bug where --custom forced the use of THREADED = False