Add verbose debugging option or build

[MobyGamer]

From @KeyJ_trbl on twitter, who reported topbench crashes on started using ao486 MiSTer core:

...it crashes if EMM386 is not not loaded, always. The command line doesn't matter because it never gets far enough to evaluate it. If EMM386 (and its EMS emulator) is loaded, however, it works like a charm (with the usual caveat that you need to use the /p option).

To try to narrow down what is going on, verbose startup debugging should be added.