perf tools: Left-align output contents

perf tools: Left-align output contents

Now perf left-aligns column headers but the contents does not.  It
should have same alignment.  This requires a change in pid sort key - it
consists of two part (pid and comm).  As length of comm can be vary it'd
be better to change the order of them.

Thanks to Jiri Olsa for pointing this out.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1406785662-5534-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>