doc: use listing instead of example
doc: use listing instead of example

rayyang2000/libbson,Machyne/libbson,ajdavis/libbson,alexeyvo/libbson,derickr/libbson,remicollet/libbson,derickr/libbson,derickr/libbson,Machyne/libbson,rayyang2000/libbson,Machyne/libbson,mongodbinc-interns/libbson,derickr/libbson,mongodb/libbson,4Second2None/libbson_tmp,mongodbinc-interns/libbson,paulmelnikow/libbson,remicollet/libbson,bjori/libbson,remicollet/libbson,paulmelnikow/libbson,rcsanchez97/libbson,bjori/libbson,jqk6/libbson,mongodbinc-interns/libbson,mongodb/libbson,paulmelnikow/libbson,Machyne/libbson,mapr/libbson,jqk6/libbson,Convey-Compliance/libbson,ajdavis/libbson,mapr/libbson,paulmelnikow/libbson,mongodb/libbson,jqk6/libbson,rcsanchez97/libbson,ajdavis/libbson,mongodbinc-interns/libbson,alexeyvo/libbson,jqk6/libbson,Convey-Compliance/libbson,rayyang2000/libbson,paulmelnikow/libbson,ksuarz/libbson,ksuarz/libbson,4Second2None/libbson_tmp,alexeyvo/libbson,remicollet/libbson,4Second2None/libbson_tmp,mapr/libbson,ksuarz/libbson,4Second2None/libbson_tmp,Convey-Compliance/libbson,bjori/libbson,rayyang2000/libbson,rcsanchez97/libbson