Add a config option for org-list-allow-alphabetical.

This fixes an issue where lines in a paragraph were incorrectly getting identified as lists because I had defaulted to assuming alphabetical bullets were allowed.

src/parser/element_parser.rs

@@ -141,7 +141,7 @@ fn _detect_element<'b, 'g, 'r, 's>(
     can_be_paragraph: bool,
 ) -> Res<OrgSource<'s>, ()> {
     if alt((
-        detect_plain_list,
+        parser_with_context!(detect_plain_list)(context),
         detect_footnote_definition,
         detect_diary_sexp,
         detect_comment,