Don't use coding category. Call

Don't use coding category.  Call
set-coding-system-priority instead of set-coding-priority.
(sort-coding-systems): Call coding-system-priority-list to get the
most preferred one.
(select-safe-coding-system): Likewise.
(reset-language-environment): Order of coding system priority
changed.  Set primary charset to iso-8859-1.
(set-language-environment-coding-systems): Call
set-coding-system-priority instead of set-coding-priority.
(get-charset-property, put-charset-property): Moved to mule.el.