argument `required-features'.
(insert-char-attributes): For each character in relation features
[->FOO or <-FOO] and `ideographic-structure', specify
- required-features pf `char-db-insert-char-spec' based on *sources.
+ required-features of `char-db-insert-char-spec' based on *sources.
* Ideograph-R057-Bow.el, Ideograph-R056-Shoot.el,
Ideograph-R055-Two-Hands.el, Ideograph-R049-Oneself.el,