Removed invalid assigned of node.node_info[:path] on virtual nodes
Created virtual nodes are not returned (and processed) twice anymore

The #create_nodes method should only return nodes that were directly
created in it. This was not the case for the path handler virtual
because it returned all created secondary nodes.
Unused paths reporting now works as expected
Made bin/webgen executable
Updated version of gem dependencies
Small modification to the Webgen Page Format

It is now allowed to use more than one spaces or tab after
the three dashes or before the dashes ending a line.