Errors in non-AI1EC plugins are hidden when AI1EC is activated

When AI1EC 2.5.36 is active, any PHP errors in unrelated plugins are hidden – because their error is caught by the AI1EC exception handler, and ignored.

In lib/exception/handler.php (line 238), the exception is (correctly) determined to NOT belong to AI1EC and (any) prior exception handler is called.
But many plugins do not create an exception handler, so there is no prior handler to call, so AI1EC ignores the exception.

Instead, in this situation, AI1EC’s handler should Throw a new exception, so that PHP’s own handler gets control, and properly documents the exception in the error log.