ps: exploit the library addition for 'cpu utilization'

This just parallels the top program by adding that new
library PIDS_UTILIZATION item to the ps repertoire. It
should be noted, however, that the new %CUU field is a
little redundant. I mean, ps already has 4 such fields
implemented identified as: '%cpu', 'c', 'cp' & 'pcpu'.

Oh well, at least the newest one offers a little value
added in the form of extra precision. We'll follow the
top lead and display results in the form of: '##.###'.

Signed-off-by: Jim Warner <james.warner@comcast.net>

ps/ps.1

@@ -1211,6 +1211,15 @@ cumulative CPU time in seconds (alias
 .BR times ).
 T}
 
+cuu	%CUU	T{
+The CPU utilization of a process in an extended "##.###" format.
+(see also
+.BR %cpu ,
+.BR c ,
+.BR cp ,
+.BR pcpu ).
+T}
+
 drs	DRS	T{
 data resident set size, the amount of physical memory devoted to other than
 executable code.