[Findit] Add iterator and crash_iterator for delta test

appengine/findit/util_scripts/crash_queries/README.md

+###################### Set up enviroment variables. #####################
+##!/bin/bash
+#
+## Notice:
+## User should copy the this part to setup_enviroments.sh script and customized 
+## the path values.
+## Source this script to setup the PYTHONPATH and other environment settings for
+## pulling data from datastore App Engine Remote API. Command:
+##   source setup_enviroments.sh
+#
+## This must be set to the directory in which Findit source code is
+## checked out, eg: ~/chrome-internal if the checkout is in
+## ~/chrome-internal/findit.
+#export FINDIT_ROOT_DIR='root/path/to/findit'
+#
+## Since findit doesn't want to cover the tests of
+#export UTIL_SCRIPTS_DIR=$FINDIT_ROOT_DIR/util_scripts
+#
+##This must be set to the third_party directory under findit.
+#export THIRD_PARTY_DIR=${FINDIT_ROOT_DIR}/third_party
+#
+## This must be set to your appengine SDK directory.
+#APPENGINE_SDK_DIR='path/to/google_appengine'
+#
+#if [[ $PYTHONPATH != *$APPENGINE_SDK_DIR* ]]
+#then
+#  export PYTHONPATH=$UTIL_SCRIPTS_DIR:$FINDIT_ROOT_DIR:$THIRD_PARTY_DIR:$APPENGINE_SDK_DIR
+#fi
+#
+## This should be set to your app id.
+#export APP_ID="your app id"
+#
+## This must be set to the directory to put local checkout in.
+#export CHECKOUT_ROOT_DIR='path/to/checkout/root/path'