Add a way to use valgrind, catchsegv or similar tool

[dajose]

Tools like valgrind and catchsegv are used in this way

valgrind --tool=memcheck gtest-binary

I think a way of using something like that would be to add a pytest_addoption on the ini like

[pytest]
harness = valgrind --tool=memcheck 

thoughts? recommendations?

[nicoddemus]

Hi @dajose,

I think that would be useful and also simple to implement.

Just to bikesheeding a bit, the option should be cpp_harness to make its relation to the plugin clear.

I probably won't have time to get to this soon, but a PR would be welcome.

cc @tadeu

[dajose]

sure :) let me give it a try