New 'Search by Range' Property for Custom Date, Integer, Money and Number Fields

Searchable custom fields where is_search is TRUE also need a 'Search by Range' property. This is applicable ONLY to Date, Number, Money, Integer data types.

Add boolean to custom_field -> is_search_range
Add conditionally displayed radio button field to create/update custom field - label = Search by Range. Default = Yes. This field is hidden on initial form display in create mode. It is unhidden IF:

• data type = Date, Money, Int, or Number AND
• Is this Field Searchable? checkbox is checked

Advanced search form displays 'From' and 'To' fields for custom fields by is_search_range = true.
Search query is modified to handle the value ranges. Ranges are should be implemented as values INCLUSIVE. For Date ranges, query should filter on x >= start_date 00:00 and x <= end_date 23:59.