Get all filter helpers

Returns all supported filter helpers. It helps to know what conditions and helpers are available when you want to <a href="/docs/api/v1/Filters#addFilter">add</a> or <a href="/docs/api/v1/Filters#updateFilter">update</a> filters. For more information, see the tutorial for <a href="https://pipedrive.readme.io/docs/adding-a-filter" target="_blank" rel="noopener noreferrer">adding a filter</a>.