Allow using the serial number for defining the bus order

If present in the interface_map of the network proposal a serial_number can be
use additionally to the Product Name for defining a specific bus_order for a
specific node.
Merge pull request #137 from rhafer/pull-req-release-pebbles-master-ead8713cdc2ce28d97bab36901b28238e32bb08e

Allow using the serial number of a node as an additional matching criteria for the bus_order [1/3]
Required syntax changes to support ruby version 1.9

"case" syntax changes and using "node.set[]=" instead of "node[]="
Added filter for operations not supported on windows.

Crowbar-hacks does not work on Windows platform.
Ohai plugins location is different on Windows.
Fixed a typo in the plugin_path for windows.