When adding a link to an item via `org-store-link`, and the link is not known
yet, the links is always put at the beginning of the list of currently known
links, as stored in `org-stored-links`. This allows to conveniently insert this
link via `org-insert-link` by just choosing the first element of the list, which
is selected by default.
However, when the link to the requested item is already present in
`org-stored-links`, the link is not pushed to the beginning of
`org-stored-links` by `org-store-link`, but kept where it is. When calling
`org-insert-link` to insert a link to the item, manual selection of the correct
link is required, which is annoying and unnecessarily interrupting the current
workflow. Even worse, when overlooking the notification that the link is
already stored, one will assume that the link to the requested item is at the
top of `org-stored-links` (which is isn't), subsequently inserting false links
when blindly calling `org-insert-link`. (Yes, this has happend to me …)
This patch fixes this issue by ensuring that links to items (regardless whether
they have already been known or not) are always put at the front of the
`org-stored-links`. This patch also removes the rarely used
`db/org-clear-stored-links` function, whose purpose was to provide some kind of
workaround, but turned out not to be convenient enough to actually be
used (because it also removed potentially useful links when clearing the cache).