Split some tests
The following tests take very long with valgrind and thus doesn't scale well on 2+ cores:
tests/test-plugin.log:46
tests/test-stats.log:97
tests/test-wget-1.log:38
The numbers are the calls to wget2. Especially test-stats.c could be split up into two or better more files, e.g. like test-stats-site.c, test-stats-tls.c, ...