Protect rasqal_strcasecmp* from appearing in standalone compile
Add STANDALONE wrappers to prevent 'main' symbol appearing in library

Make rasqal_xsd_check_double_format an internal non-static symbol

Fixes Issue #0000564
http://bugs.librdf.org/mantis/view.php?id=564
Rewrite test code to use usual xsd decimal constructor / destructors
Wrap more xsd_decimal code for internal use, not in test runner
Add STANDALONE if/ifndef STANDALONE ... endif comments