* org-feed.el (org-feed-format-entry): Require `org-capture'.
Expand Elisp %(...) templates.
(org-feed-default-template): Update docstring.
* org-capture.el (org-capture-expand-embedded-elisp): New
function.
(org-capture-fill-template): Use it.
(org-capture-inside-embedded-elisp-p): New function to tell if
we are within an Elisp %(...) template.