Unit tests

- The dependencies.t unit test script failed to unlink completed.data,
  which polluted the subsequent test script.
- Simplified some Perl in start.t.
- Allowed for line wrapping in start.t.

src/tests/export.yaml.t

@@ -49,7 +49,6 @@ if (open my $fh, '<', './export.txt')
   @lines = <$fh>;
   close $fh;
 }
-
 like ($lines[0],  qr/^%YAML 1.1$/,            'export.yaml line 0');
 like ($lines[1],  qr/^---$/,                  'export.yaml line 1');
 like ($lines[2],  qr/^  task:$/,              'export.yaml line 2');