Breakpoints should be illustrated somehow in GUI

[jrgreen7]

When a breakpoint is added to a program in Libra, there should be some GUI indicator of its presence. Likewise, when a breakpoint is removed...

[jrgreen7]

Wait a second, NOW I'm seeing breakpoints with red highlighting. Something going on here, since it was not displaying the highlighting a moment ago. Did not restart Libra, but I did reload the OBJ file.

[rdnelson]

It looks like if you have the line with the breakpoint selected, there is no indication that there's a BP on that line.

We'll highlight the line in purple if there's a breakpoint on the selected line.