unictype/bidi*: Rename functions.

unictype/bidi*: Rename functions.

* lib/unictype.in.h (uc_bidi_class_name, uc_bidi_class_byname,
uc_bidi_class, uc_is_bidi_class): New declarations.
* lib/unictype/bidi_byname.c (uc_bidi_class_byname): Renamed from
uc_bidi_category_byname.
(uc_bidi_category_byname): New function.
* lib/unictype/bidi_name.c (u_bidi_class_name): Renamed from
u_bidi_category_name.
(uc_bidi_class_name): Renamed from uc_bidi_category_name.
(uc_bidi_category_name): New function.
* lib/unictype/bidi_of.c (uc_bidi_class): Renamed from
uc_bidi_category.
(uc_bidi_category): New function.
* lib/unictype/bidi_test.c (uc_is_bidi_class): Renamed from
uc_is_bidi_category. Invoke uc_bidi_class.
(uc_is_bidi_category): New function.
* tests/unictype/test-bidi_byname.c (main): Test uc_bidi_class_byname
instead of uc_bidi_category_byname.
* tests/unictype/test-bidi_name.c (main): Test uc_bidi_class_name
instead of uc_bidi_category_name.
* tests/unictype/test-bidi_of.c (main): Test uc_bidi_class instead of
uc_bidi_category.
* tests/unictype/test-bidi_test.c (main): Test uc_is_bidi_class
instead of uc_is_bidi_category.