Configurable setting to allow operators to require admin users provide search criteria first, before loading any data

Summary
=======
Have a configurable setting to allow operators to require admin users to provide search criteria first before loading any data.

Motivation
========
Currently if there is a large amount of resources in the environment, the admin views take too much time to load. Making a series of API calls to populate the table with the first 20 of say 1000 items is wasteful and has a low likelihood of success.
Horizon needs to have a configurable feature that allows requiring admin users to provide a set of filters before loading the data in the views, so that the user only gets what he/she needs.

Description
=========
- There will be a configurable setting that can be set in the local_settings.py file:
  FILTER_DATA_FIRST={
      'admin.instances': False,
      'admin.volumes': False,
      'admin.networks': False,
      'admin.images': False
  }
- The default value of the dict attributes will be False
- A set of new filter inputs will be displayed in the admin views (Investigate APIs server side filtering first)
- If the FILTER_DATA_FIRST key,value is True; then the admin views will display an empty table and a message notifying the user that a search criteria must be applied first
- The change will target Instances, Volumes, Images, Networks and Routers admin views
- At least one filter must be selected before submitting the search criteria

UX
===
Change targeted views behavior to display an empty table and a message to inform the user about specifying a search criteria first
if the configuration variable is set to True

Wireframes, Mocks, Videos and UI Markup
---------------------------------------------------------
If the FILTER_DATA_FIRST key-value is set to True the targeted view will show an empty table but with an embedded text message saying "Please specify a search criteria first."
A search criteria filtering input(s) will be available to the user as part of the standard table filtering.

Outside Dependencies
==================
collect information about API server side filtering for Instances, Volumes, Images and Networks
and implement available filters

Doc Impact
=========
- Changes to settings file will be required to add the new configuration value. Need to document this new variable
- The data loading behavior of admin views will change when the new configuration value is set to True. Need to document this behavior.
- Release Note item also needs to be added.