My nasty hacks

Apologies for the ham-fisted code in the patch. However it works!

From the testing I've done request_pfe_execute accepts wither a single String or an Array of Strings in the :command argument. I've also added error raising if either :target or :command are missing; the API is pretty meaningless without them.

I've also updated Netconf::RpcError#to_s to include the RPC response. It gives the user a clue why the RPC failed.