Refactor.

Refactor.

* gettext-tools/src/cldr-plural.y: Untabify.
(struct cldr_plural_parse_args): New type, moved here from
gettext-tools/src/cldr-plural-exp.h.
(cldr_plural_parse): New function, moved here from
gettext-tools/src/cldr-plural-exp.c.
* gettext-tools/src/cldr-plural-exp.h: Reorder declarations.
(struct cldr_plural_parse_args): Remove declaration.
* gettext-tools/src/cldr-plural-exp.c: Don't include cldr-plural.h. Reorder
functions.
(cldr_plural_parse): Remove function.