[Findit] Factoring the gitiles (etc) stuff out into its own directory

appengine/findit/waterfall/identify_try_job_culprit_pipeline.py

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from collections import defaultdict
 import copy
 import logging
 
 from google.appengine.ext import ndb
 
-from common.git_repository import GitRepository
+from lib.gitiles.git_repository import GitRepository
 from common.http_client_appengine import HttpClientAppengine as HttpClient
 from common.pipeline_wrapper import BasePipeline
 from common.waterfall import failure_type
 from model import analysis_approach_type
 from model import analysis_status
 from model import result_status
 from model.wf_analysis import WfAnalysis
 from model.wf_try_job import WfTryJob
 from model.wf_try_job_data import WfTryJobData
 from waterfall.send_notification_for_culprit_pipeline import (
@@ skipping 378 matching lines @@
     UpdateWfAnalysisWithTryJobResult()
 
     # TODO (chanli): Update suspected_cl for builds in the same group with
     # current build.
     # Updates suspected_cl.
     UpdateSuspectedCLs()
 
     _NotifyCulprits(master_name, builder_name, build_number, culprits,
                     heuristic_cls, compile_suspected_cl)
     return result.get('culprit') if result else None