README: add compile example.
README: add compile example.

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