pidof: modify to utilize the new procps_pids interface
As an additional test of the viability of the new pids
API, the pidof program has now been converted. As part
of that effort, several library changes were prompted:
. individual reads were added as an alternative to the
all encompassing (maybe over broad?) 'reap' provision.
. an alternate version of cgroup, cmdline plus environ
has been added to represent actual vectorized strings.
Signed-off-by: Jim Warner <james.warner@comcast.net>