perf scripts python: Add initial script file with usage information

Added necessary modules, including the Perf-Trace-Util
library, and defines the required functions and variables
for using perf script python. The perf_trace_context and
Core modules for tracing and processing events has been
also imported. Added usage information.

Signed-off-by: Anup Sharma <anupnewsmail@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/f2f1a62f1cc69f44a5414da46a26a4cf124d2744.1689961706.git.anupnewsmail@gmail.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>