Adding handling for '-h' and '-v' options to invoke help and version
command respectively.

Current behaviour is:

   $ perf -v
   Unknown option: -v

    Usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS]
   $ perf -h
   Unknown option: -h

    Usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS]

New behaviour:

  $ perf -h

   usage: perf [--version] [--help] [OPTIONS] COMMAND [ARGS]

   The most commonly used perf commands are:
     annotate        Read perf.data (created by perf record) and display annotated code
     archive         Create archive with object files with build-ids found in perf.data file
     bench           General framework for benchmark suites
   ...

  $ perf -v
  perf version 4.3.rc3.gc99e32

Updated man page.
Requested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-10-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>