test environment setup for development with IDE

 Test::InDistDir helps run test scripts in IDEs like Komodo.
 .
 It automatically moves up one directory when it cannot see the
 test script in "t/$scriptname" and includes 'lib' in @INC when
 when there's no blib present. That way the test ends up with
 almost the same environment it'd get from EUMM/prove/etc.,
 even when it's actually run inside the t/ directory.