Make http charset detection code more robust. This addresses issue #321.

This allows correct character set detection and parsing for the following domains and more. I've added tests for all new functionality and all old tests are passing as well, including the integration tests. I added small integration tests fpr the special domains. I would not mind if they are deleted because the tend to be flaky (changing domains content, on/offline state) and the real code is unit tested I put them to prove that the domains are really working.

9kuhkep.net
www.a-bright.org
aawdc.net
aaptsdassn.org
aamo.info
aaconsult.biz
a-event-z.ch
aastmultimedia.com
aag-ye.com
aapm.biz

FYI: UrlConnectTest.fetchBaidu is broken, even before I was starting to work on this. I was not totally sure how to fix the test.

Still broken: http://a-event-z.ch  I guess this needs a fix to the parse to handle a broken meta charset property properly. Please have a look at the url to see the problem.