Memory_tracker imports psutil, but does not run inside a pip/virtualenv
so the system provided psutil library needs to be provided. This
is matching what is done for other non-SUSE distributions
Change-Id: I96f944730dc8644333d906d71339351b29b03e08
pidstat data isn't exceptionally useful, it's lots of lines, and
seems to be missing some of the most critical one.
dstat is kind of like sysstat, except the formatting is much better.
It also supports advanced features like the top CPU using process
at every interval.
put this behind the sysstat variable, as we'll probably want to
replace sysstat & pidstat with this if it works
Change-Id: I48dc22a0a7e63fe3abb527646cc70525998a7d85