Fix several Package Menu and Finder bugs.

Fix several Package Menu and Finder bugs.

* finder.el: Load finder-inf using `require'.
(finder-list-matches): Sorting by status is now the default.
(finder-compile-keywords): Simpify printing.

* emacs-lisp/package.el (package--read-archive-file): Just use
`read', to avoid copying an additional string.
(package-menu-mode): Set header-line-format here.
(package-menu-refresh, package-menu-revert): Signal an error if
not in the Package Menu.
(package-menu-package-list): New var.
(package--generate-package-list): Operate on the current buffer;
don't assume that it is *Packages*, since the user may rename it.
Allow persistent package listings and sort keys using
package-menu-package-list and package-menu-package-sort-key.
(package-menu--version-predicate): Fix version calculation.
(package-menu-sort-by-column): Don't select the window.
(package--list-packages): Create the *Packages* buffer.  Set
package-menu-package-list-key.
(list-packages): Sorting by status is now the default.
(package-buffer-info): Use match-string-no-properties.
(define-package): Add a &rest argument for future proofing, but
don't use it yet.
(package-install-from-buffer, package-install-buffer-internal):
Merged into a single function, package-install-from-buffer.
(package-install-file): Caller changed.

Also, fix headers for hfy-cmap.el and ps-print.el.