(ids-index-store-char): Use `get-char-attribute' instead of

(ids-index-store-char): Use `get-char-attribute' instead of
`char-feature' to refer `ideographic-products' to avoid infinite loop;
ignore COMPONENT's substructure.
(ids-index-store-structure): Ignore char-ref format.
(ids-insert-chars-including-components): New function.
(ids-find-chars-including-components): Use
`ids-insert-chars-including-components'.