OProfile => XenGatherer

I extended the XenGatherer prototype such that when it is started opcontrol starts gathering information about cache misses (event LLC_MISSES):

• opcontrol --reset
• opcontrol --start-daemon --event=LLC_MISSES:10000 --xen=... --vmlinux=...
• opcontrol --start

When the XenGatherer tool is stopped, opcontrol is stopped as well:

• opcontrol --stop
• opcontrol --shutdown

And when you choose to make a report (throught the XenGatherer CLI) the retrieved information is written to file. The information gathered by OProfile is requested by the following command:

• opreport event:LLC_MISSES

An updated version of the Python source files can be found here.