The summary of the following changes:

The summary of the following changes:
(1) Make all coding systems (including aliases and subsidiaries)
directly have coding-spec vector in `coding-system' property.
(2) Properties of a coding system (except for `coding-system' and
`eol-type') is embeded in PLIST slot of coding-spec vector.
(coding-spec-plist-idx): Initialize to 3.
(coding-system-spec-ref): Deleted.
(coding-system-spec): Moved from src/coding.c.
(coding-system-type): Adjusted for the above change.
(coding-system-mnemonic): Likewise.
(coding-system-doc-string): Likewise.
(coding-system-flags): Likewise.
(coding-system-eol-type): Likewise.
(coding-system-category): Likewise.
(coding-system-get, coding-system-put, coding-system-category):
New functions.
(coding-system-base): Moved from mule-util.el and adjusted for the
above change.
(coding-system-parent): Make it obsolete alias of
coding-system-base.
(make-subsidiary-coding-system): Adjusted for the above change.
Update coding-system-list and coding-system-alist.
(make-coding-system): Likewise.
(set-buffer-file-coding-system): Typo in doc-string fixed.
(after-insert-file-set-buffer-file-coding-system): Change
enable-multibyte-characters only when
find-new-buffer-file-coding-system returns non-nil value.
(find-new-buffer-file-coding-system): Adjusted for the abobe change.