Increment version number to 2.1, and use a literal

Increment version number to 2.1, and use a literal
rather than RCS $Id$.  Remove autoloads for mailcrypt and crypt++.
Require pgg, pgg-gpg during compilation.
(allout-version): Increment version number to 2.1, and use a literal
rather than RCS $Id$.
(allout-default-encryption-scheme): Removed.
(allout-passphrase-verifier-handling): Renamed from
allout-key-verifier-handling.
(allout-passphrase-verifier-string): Renamed from allout-key-verifier-string.
(allout-file-passphrase-verifier-string): Renamed from
allout-file-key-verifier-string.
(allout-enable-file-variable-adjustment): Simplified.
(allout-passphrase-hint-handling): Renamed from
allout-key-hint-handling and simplified.
(allout-passphrase-hint-string): Renamed from allout-key-hint-string.
(allout-init): Use `find-file-hook' if available, otherwise `find-file-hooks'.
(allout-mode): Use `write-file-functions' if available, otherwise
`local-write-file-hooks' and, instead of making auto-save-hook
buffer local, make the write-file-hook activity contingent to allout-mode.
(allout-mode): Use key-binding substitution placeholders in the docstring.
(allout-kill-line): Spell-out kill ring data structure mutation
instead of using byte-compiler-complaint-provoking `pop'.
(allout-insert-listified): Use `insert' rather than `insert-string'
(allout-toggle-current-subtree-encryption): Updated docstring,
adjust to new gpp-based encryption, use new `allout-encrypted-topic-p'.
(allout-encrypt-string): Totally revamped vis new underlying encryption
facilities.
(allout-mc-activate-passwd): Removed.
(allout-obtain-passphrase): New, more or less replaces
allout-mc-activate-passwd.
(allout-encrypted-key-info): More or less replaces allout-encrypted-text-type.
(outlineify-sticky, outlinify-sticky): Add autoload cookie.
(my-mark-marker): Use `(featurep 'xemacs)' to distinguish between Emacs and
XEmacs.