Function: Clean up an array, comma- or space-separated list of strings.

Function: Get the user object, if the ID is valid.

Function: Registers a new field on an existing BuddyPress object.

Function: Validate member_type input.

Function: Clean up group_type input.

Function: Validate group_type input.

Function: Get user URL.

Function: Set headers to let the Client Script be aware of the pagination.

Function: Convert the input date to RFC3339 format.