bloatpad: move into private subdir

bloatpad: move into private subdir

Move bloatpad to ./examples/bp/ so that we can start treating it as more of a
"normal" app instead of just jamming everything into a single .c file.

We don't use the name "bloatpad" for the directory in order not to
create 'git pull' pain with the probably-already-existing executable of
the same name.

https://bugzilla.gnome.org/show_bug.cgi?id=722092