Set breakpoints if modules become available

[TheGeorge]

With #1373 resolved, we can now set the break points to not existing modules, but when they become available,e.g. though loading binaries into the code server, or adding code paths, we now need the user to set them again.

We should at least support the scenario when the code path is extended:

• trace various methods from the code module and erlang:load_module, and erl_prim_loader:get_file
• replay breakpoints on when these functions are called