commit: stable MSVC 5 build fix

[Kenneth J. Davis]

Changed line 276 in ut_base64.cpp 
from:
        while (UT_UCSChar ucs2 = UT_UCS2Stringbuf::UTF8_to_UCS2 (b64ptr, b64len))
to:
        UT_UCSChar ucs2;
        while (ucs2 = UT_UCS2Stringbuf::UTF8_to_UCS2 (b64ptr, b64len))


Nightly Win32 stable builds should once again be available 
(at least until the next build breakage -- so until tommorrow I guess :-)

Jeremy