restructured, largely rewritten without the bugs and

restructured, largely rewritten without the bugs and
extended to cover over 15 shells.  Most variables can now work as a
lookup table, and, unless set by user, do.
(sh-mode-syntax-table): Possibly multiple tables.
(sh-shell): Set initially so shell or other libraries may use features.
(sh-assignment-regexp): Replaces `sh-assignment-space'.
(sh-here-document-word): Set to more common "EOF".
(sh-variables): Changed semantics.
(sh-font-lock-keywords): Much nicer.
(sh-ancestor-alist, sh-alias-alist, sh-shells, sh-abbrevs)
(sh-dynamic-complete-functions, sh-require-final-newline)
(sh-comment-prefix, sh-indentation, sh-header-marker, sh-builtins)
(sh-leading-keywords): New variables.
(sh-use-prefix, sh-find-file-modifies, sh-query-for-magic)
(sh-magicless-file-regexp, magic-number-alist, sh-executable)
(sh-chmod-argument, sh-shell-is-csh, sh-tab-width)
(sh-sh-font-lock-keywords, sh-ksh-font-lock-keywords)
(sh-bash-font-lock-keywords, sh-csh-font-lock-keywords)
(sh-tcsh-font-lock-keywords): Variables deleted, see also executable.el.

(sh-mode): Shell dependent code moved to `sh-set-shell'.
(sh-feature, sh-abbrevs, sh-syntax-table, sh-append, sh-modify): New
functions.
(sh-execute-region): New command.
(sh-indexed-loop): Far more efficient code generated for sh.
(sh-repeat, sh-tmp-file, sh-while-getopts): New skeletons.
(sh-or-other-mode, define-sh-skeleton, sh-executable, sh-chmod)
(sh-query-for-variable): Command deleted.