(cpp-edit-list): Move definition toward start of file.

(cpp-edit-list): Move definition toward start of file.
(cpp-face-type-list, cpp-writable-list, cpp-button-event)
(cpp-edit-buffer, cpp-branch-list, cpp-face-default-list)
(cpp-face-light-name-list, cpp-face-dark-name-list)
(cpp-face-light-list, cpp-face-dark-list, cpp-face-mono-list)
(cpp-face-none-list, cpp-face-all-list, cpp-overlay-list): Likewise.

(cpp-highlight-buffer): Rename stack to cpp-state-stack.
(cpp-parse-open, cpp-parse-close): Likewise.
(cpp-push-button, cpp-choose-symbol): Rename data to cpp-callback-data.
(cpp-state-stack, cpp-callback-data): Add defvars.