[fr] allow overriding the likely unintended consequence of org-export-with-tasks

[Samuel Wales]

when org-export-with-tasks is set to nil, tasks will not be exported,
but non-task entries will.

you can make non-exported todo items and notes about your exported text.

* REF this is the top level of the subtree
*** NOTE this is just a note and should not be exported
*** but this i want to export of course

you can specify other values for the variable that have a similar
effect.  let's use nil for this example.

this is highly useful, but in my case, there is an unintended
consequence.   the REF todo kw prevents anything from being exported,
for subtree or region export.  not exporting is not a useful behavior.
i would prefer the top level of the subtree to be exported in all
cases, because i have asked org to export.  it does not matter what kw
it is set to or what the variable is set to.

technically, at least for subtree export, org is doing what the
variable says on the tin, but it is not useful here.

therefore, in order to work around the lack of exporting, i.e. the
unintended consequence, you have to temporarily remove the todo kw,
export, then restore kw.  even exporting a region starting after the
REF kw does not work.  should it?

regardless of the answer, it would be great if it were /possible/ to
export the top level despite its having a todo kw.