gdb_get_breakpoint_info

[Tom Tromey <tromey at redhat dot com>]

I just submitted a PR based on my findings about gdb_get_breakpoint_info.
(It's documentation is broken and we have Tcl code that works as
though the docs were correct.)

What if we changed gdb_get_breakpoint_info to take the name of an
array as an argument.  Then it could set array elements using
intelligently-named keys.  We could expand the key list over time
without necessarily updating every single piece of code that uses the
function.

Comments?

Tom