Display quotes in key-bindings as straight quotes

Display quotes in key-bindings as straight quotes

* lisp/org-agenda.el (org-agenda-show-the-flagging-note):
* lisp/org-footnote.el (org-footnote-goto-definition):
* lisp/org-table.el (org-table-edit-formulas): Fix straight quotes
  rendered as curvy quotes in echoes messages (in emacs 25.1).
* lisp/org-table.el (org-table-align): Fix straight quotes rendered as
  curvy quotes in help echo (in emacs 25.1).

* lisp/org-protocol.el (org-protocol-create-for-org):
* lisp/org-table.el (org-table-sum): Minor reformatting.

The below thread discusses why these changes were needed especially when
using emacs 25.1 or newer emacsen (that added support for rendering
back-quotes and straight quotes as left/right curvy quotes by default):
http://thread.gmane.org/gmane.emacs.orgmode/105594

Fix the quote style displayed when key-bindings are shown in
the echo via (message .. (substitute-command-keys ..)).

So below will render that single quote as curly.

(message "C-c '")

The fix (Reference:
https://lists.gnu.org/archive/html/bug-gnu-emacs/2015-10/msg00234.html)
is to print that quote verbatim using the "%s" modifier:

(message "%s" "C-c '")

Also an help-echo text property value was fixed in `org-table-align'.
`substitute-command-keys' should not be used in that.  Instead \\[COMMAND]
should be used directly in the string.