Add an option to silence OutputDebugString output

[aitap]

Hi! I would like to use catchsegv to debug crashes during automatic checks of R packages on Windows.

Some applications used by R during the check (MSYS compilers, MiKTeX) output a lot of distracting information via OutputDebugString(), so I added a flag to the debugger options and to catchsegv to silence it.

Please let me know if my changes need to be improved before they can be merged.

[jrfonseca]

Makes sense. I primarily use catchsegv to debug components which log messages through OutputDebugString, hence the current behavior, but I can see how that would only get in the way for components which log to stderr.

If you could update https://github.com/jrfonseca/drmingw/blob/master/README.md#catchsegv too, it would be perfect.

Thanks.

[aitap]

Thanks for the quick reply! I've edited README.md and reworded the option description to avoid repetition.

[jrfonseca]

There are some issues with the build, unrelated to this change. (I suspect some upstream CMake change broke something.) I want to sort those out before merging this.

[aitap]

Many thanks for merging this pull request! I was hoping to show off catchsegv at work on the big auto-check machine, but that will take more diplomacy and effort. My colleagues and me are using catchsegv locally and are very grateful for its existence.