r34417: Normalization data files updated to Unicode 5.1.0; passes the automated tests.

Seem to have long since lost the script I originally used to generate the Utf8Case.php mapping file, which appears not to have been updated since 2002 or so. :)
Made a new one and moved it into the UtfNormal sub-library.

Note a couple limitations:

• Case mapping (still) uses only the 1:1 simple mappings. Any full or locale-specific mappings are ignored.
• These case mappings are not used anyway when the PHP mbstring extension is available; mbstring's case conversion functions are used instead, with whatever version of Unicode support and whatever complex mapping support they may or may not have.
• The generated Utf8Case.php file is not used directly -- you must also regenerate the serialized version in the 'serialized' directory after updating it to a new Unicode version.