Ignorable, contextual test support for Module::Install
Description
This allows extra_tests; to be declared in Makefile.PL, indicating that the
test files found in the directory ./xt should be run only in certain
instances:
./xt/author - run when the tests are being run in an author's working copy
./xt/smoke - run when the dist is being smoked (AUTOMATED_TESTING=1)
./xt/release - run during "make disttest"