ii-ob-clear-results (active-region && current-heading+subheadings)

[hh]

Similar to ii-ob-clear-all-results:
https://github.com/ii/doom-config/blob/canon/config.el#L165-L171

• Please write an ii-ob-clear-region-results on the active region with: https://www.gnu.org/software/emacs/manual/html_node/elisp/Interactive-Call.html#index-call_002dinteractively

• Please write an ii-ob-clear-current-heading-and-subhead-results:

[zachmandeville]

Implemented in #12