check_esxi_hardware

Improve pywbem exception handling across old (< 1.0.0) and newer (>= 1.0.0) pywbem versions.

Also handle HTTPError exception. This is useful when the plugin is mistakenly pointed to a HTTP endpoint which does not serve any CIM elements (ESXi HTTPS UI for example).

Attention: The plugin requires the Python module "packaging" from now on!