Updated tests & results: Language-dependent styling

These tests examine whether a user agent is capable of styling elements in XHTML 1.0 served as text/html using CSS selectors that examine the language declared in element attributes.

All tests have been rewritten, resulting in some small corrections and changes to the previous set of tests, and improvements to the page styling. Additional tests were added to check behaviour with regard to the script tags in BCP 47. Also, a whole set of tests were developed for XHTML 1.1 (served as XML). The results page was rewritten to reflect the behavior of the latest versions of a number of major browsers (including IE8 beta, which now supports :lang). [search key: test-css-lang]