FindCommerce initialization issues

Description

To fix bug COM-2912 and COM-2915, we try and catch exceptions when applying client conventions during initialization. This, however, does more harm than good. The error logs can easily slip out of attentions, and the site appears to run normally.

But because the conventions, including the custom ones, were not properly applied, any index happens during that session (until the site restarts, if ever) will be fundamentally broken and searches will return incorrect results, and that would be very hard to diagnose.

The fix should be catch only WebException, with an option to by pass it, consciously. Other exceptions should fail to start the site.

Fix note: If the appSetting episerver:findcommerce.IgnoreWebExceptionOnInitialization is set to true, the error will be logged instead of thrown as an exception. If the logger is not enabled with at least Error level, the exception will be thrown regardless of the setting.