Add salt.utils.traverse_dict_and_list()

Add salt.utils.traverse_dict_and_list() and use it in modules.pillar.get() and modules.grains.get()
* fix pylint errors
* use traverse_dict_and_list() in modules.config
+ add test_traverse_dict_and_list
+ use traverse_dict_and_list() in more get routines
Merge pull request #13446 from anylain/add_traverse_dict_and_list

Add salt.utils.traverse_dict_and_list()