This is the first step of making lldb able to create target-specific things
(e.g. breakpoints, stop-hooks) before we have any targets - for instance in
your ~/.lldbinit file.  These will then get copied over to any new targets
that get created.  So far, you can only make stop-hooks.

Breakpoints will have to learn to move themselves from target to target for
us to get them from no-target to new-target.

We should also make a command & SB API way to prime this ur-target.