Enable regex search (#4566)

* Adds custom search filter to allow 'regex' searching of results

* Specify if "shell" can access database for certain commands

* Bug fix for settings API

- Do not allow cache on detail endpoints
- Was causing strange error conditions with missing or duplicate PK values

* Adds user setting to control regex search

* Enable regex for search queries

- bootstrap tables
- search preview

* Pass search options through bettererer

* Refactor API endpoints to use new filter approach

* Bump API version

* Add "whole word" search

- Closes https://github.com/inventree/InvenTree/issues/4510

* Handle case where existing fields are empty

* pop > get

InvenTree/label/api.py

@@ -8,12 +8,12 @@ from django.utils.decorators import method_decorator
 from django.views.decorators.cache import cache_page, never_cache
 
 from django_filters.rest_framework import DjangoFilterBackend
-from rest_framework import filters
 from rest_framework.exceptions import NotFound
 
 import common.models
 import InvenTree.helpers
 from InvenTree.api import MetadataView
+from InvenTree.filters import InvenTreeSearchFilter
 from InvenTree.mixins import ListAPI, RetrieveAPI, RetrieveUpdateDestroyAPI
 from InvenTree.tasks import offload_task
 from part.models import Part
@@ -124,7 +124,7 @@ class LabelListView(LabelFilterMixin, ListAPI):
 
     filter_backends = [
         DjangoFilterBackend,
-        filters.SearchFilter
+        InvenTreeSearchFilter
     ]
 
     filterset_fields = [