Patch proposal for org-capture-set-target-location

The idea is that when somebody use the function or file+function targets you can make the template subheading from the heading where the custom-function set the point.
org-capture-set-target-loction force the org-capture-plist :exact-position to (point).

So the template is inserted in the same level not as subheading

With my patch the custom-function can (org-capture-put :exact-position nil), and now if point its placed in a heading the template is created as his subheading.

For a use case can look at the following emacs.stackexchange question

http://emacs.stackexchange.com/questions/3750/org-capture-files-entry-under-wrong-datetree/3765#3765

Thanks.

Roberto Huelga.