Prevent the PCRE error: preg_match(): Compilation failed: disallowed Unicode code point (>= 0xd800 && <= 0xdfff)

- removed the testCom() test as it did not fail even when other tests were failing (the Unicode error is related to IDN domain, not to standard .com domain)
- Fixes #322
Merge pull request #472 from mhujer/322-fix-com-idn-pcre

Prevent the PCRE error: preg_match(): Compilation failed: disallowed Unicode code point (>= 0xd800 && <= 0xdfff)