update sql_schema #69
set RewriteBase in .htaccess. now it works without setting a global apache include path, so pls do not set any include path if not necessary for other tasks #69
update ExceptionHandling: add some Exceptions and add logic for throwing exceptions and give the error back to the client.
the client should decide what to do when the returned json contains an error (like a prompt or something). also its beneficial for us to know whats went wrong in backend. if you get/find uncaught exceptions pls report it or fix it on your own. #74 fixed