RssReader: use charset reported by http server
ScraperUrl: use charset reported by http server
XBMCTinyXML::LoadFile: use charset reported by http server
XBMCTinyXML::Parse: fix m_UsedCharset if functions called without TIXML_ENCODING_UNKNOWN
TuxBoxUtil: use charset reported by http server
TuxBoxDirectory: use charset reported by http server
HTTPDirectory: use charset reported by http server
DAVDirectory: use charset reported by http server