HARNESS_PERL_SWITCHES no longer set so Devel::Cover spams child-parent comunication

[baynes]

As of commit fbe955b ( pull request #63, issue #62 ) the environment variable HARNESS_PERL_SWITCHES is no longer set to "-MDevel::Cover".

But Devel::Cover looks fot that being set and goes into silent mode if it is set.

If a unit test involves forking a child and the parent reading the standard output from the child, then Devel::Cover not being in silent mode means it spams the ouput from the child, the parent objects and the test fails.

It has taken two days of investigation into why a working unit test stoped working on upgrading.

Please reinstate the setting of the environment variable, or work with Devel::Cover developers to find another way to shut it up.