* modes.texi (Hooks): Clarify.
(Major Mode Basics): Mention define-derived-mode explicitly.
(Major Mode Conventions): Rebinding RET is OK for some modes.
Mention change-major-mode-hook and after-change-major-mode-hook.
(Example Major Modes): Moved to end of Modes section.
(Mode Line Basics): Clarify.
(Mode Line Data): Mention help-echo and local-map in strings.
Explain reason for treatment of non-risky variables.
(Properties in Mode): Clarify.
(Faces for Font Lock): Add font-lock-negation-char-face.