class_docstr: Statefully sort schema by priority where 0 is the highest priority
  and the lowest priority is any positive numeric value.
  In the event that no priority is specified for a schema,
  it will be placed at the end after all schema with a priority defined.
  If no priority or equal priority is specified for multiple schema, they will
  be sorted in the order they were encountered. The intent of the statefulness
  of this function is that there is no arbitrarily enforced upper bound for priority.
code: def __init__(self):
      # Set a default index to -1
      self.max_index = -1
  
imports: from collections import defaultdict, OrderedDict
  import json
  import os
  import re
  from streamalert.shared import CLUSTERED_FUNCTIONS
  from streamalert.shared.exceptions import ConfigError
  from streamalert.shared.logger import get_logger
label_desc: Use image node_id 1 to create a new SchemaSorter object  with example: obj = SchemaSorter()