Change: (org-ql-search-block) Sort by org-ql sorter, etc.

[alphapapa]

See #79.

• Confirm that this still works since rebasing.
• Update documentation.

[jirijakes]

Oh, this would be a useful change.

I just applied this patch to master, using Org mode version 9.8-pre (9.8-pre-n/a-g53cd3f) (git) and seems to be still working, both header and sorting:

(org-ql-block '((and (tags "mytag") (not (done)))
                :header "My Tag"
                :sort (priority reverse)))

[chaoflow]

"Should we really use org-ql-block-header' AND header', or just one of them?"

@alphapapa Thank you for adding sorting! If org-ql-block-header does not add functionality over :header, I suggest to only support :header.

[jwiegley]

Would love to see this merged!