More sophisticated indentation of cpp directive.

More sophisticated indentation of cpp directive.
(antlr-indent-at-bol-alist): New user option.
(antlr-indent-line): Use it.
(antlr-indent-style): New user option.
(antlr-mode): Use it.
(antlr-indent-item-regexp): Customize.

Syntax highlighting changes.
(antlr-font-lock-literal-regexp): New user option.
(antlr-font-lock-syntax-face): New face used for :, |, ....
(antlr-font-lock-default-face): New face.
(antlr-font-lock-additional-keywords): Use them.

New command to insert options -- variables.
(antlr-mode-map): New binding [C-c C-o].
(antlr-mode-menu): New submenus.
(antlr-options-use-submenus): New user option.
(antlr-tool-version): New user option.
(antlr-options-auto-colon): New user option.
(antlr-options-style): New user option.
(antlr-options-push-mark): New user option.
(antlr-options-assign-string): New user option.
(antlr-options-headings): New variable.

New command to insert options -- specific.
(antlr-options-alists): New variable.
(antlr-read-value): New function.
(antlr-read-boolean): New function.
(antlr-language-option-extra): New function.
(antlr-language-limit-n-regexp): Change default to higher LIMIT.
(antlr-c++-mode-extra): New function.
(antlr-grammar-tokens): New function.
(antlr-imenu-create-index-function): New optional argument.

New command to insert options -- functions.
(antlr-insert-option): New command.
(antlr-insert-option-interactive): New function.
(antlr-options-menu-filter): New function.
(antlr-option-kind): New function.
(antlr-scan-lists): New alias.
(antlr-scan-lists-internal): New function.
(antlr-skip-file-prelude): Hack for special SKIP-COMMENT.
(antlr-option-level): New function.
(antlr-syntactic-grammar-depth): New function.
(antlr-option-location): New function.
(antlr-insert-option-do): New function.
(antlr-option-spec): New function.
(antlr-version-string): New function.
(antlr-insert-option-existing): New function.
(antlr-insert-option-space): New function.
(antlr-insert-option-area): New function.

New electric keys ":;|&(){}", TAB works better
with narrowing.  Menu change.  Miscellaneous.
(antlr-mode-menu): Include "Indent Region" and "Customize Antlr".
(antlr-mode-map): New bindings for characters in ":;|&(){}".
(antlr-electric-character): New command.
(antlr-class-header-regexp): New variable.
(antlr-font-lock-additional-keywords): Use it.
(antlr-imenu-create-index-function): Use it.
(antlr-file-dependencies): Use it.
(antlr-indent-line): Also works with restrictions.
(antlr-indent-command): Interactive spec - changes the buffer.
(antlr-language-for-option): Deletia.
(antlr-language-option): New function, defined instead.
(antlr-mode): Use it.