perf python: Add perf.tracepoint method

To get id of the tracepoint from subsystem and name strings. The
interface is:

  id = perf.tracepoint(sys, name)

In case of error -1 is returned.

It will be used to get python tracepoint event's config value for
tracepoint event.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1468148882-10362-7-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

path: root/NEWS

2003/09/04 - Release of version 15.5.
2002/08/15 - Release of version 15.4.
2001/07/02 - Release of version 15.3. 
2000/04/18 - Release of Version 13.0 into Open Source. Initial Linux port