ignore expected errors on Windows

[vinipsmaker]

On Windows, the recv_from operation on the UDP socket may return the
following errors, which are expected and should be ignored:

• 10054 (WSAECONNRESET): Windows can send this error if a previous send
  operation resulted in an ICMP Port Unreachable. And if it's a loopback
  interface, it can know whether there is already another end to
  communicate.
• 10040 (WSAEMSGSIZE): This error was randomly appearing in a test that
  I conducted. Not really sure why it's happening. The frequency
  decreased when I increased the receive buffer size, but it was not
  important to get a network up and running.

Without these changes, it was impossible to get a relatively large
network running without issues. By large I mean a test that might be too
bursting for a single machine to run.

More references:

• http://stackoverflow.com/questions/30749423/is-winsock-error-10054-wsaeconnreset-normal-with-udp-to-from-localhost#comment49588739_30749423
• Adds uTP network test maidsafe-archive/crust#454

[vinipsmaker]

Original commit (which was applied on top of a branch with the set-read-timeout patchset and therefore is a little different): vinipsmaker@64fddb4

[vinipsmaker]

The failure on CI is thanks to a problem with Rust nightly. If you change the CI to use Rust stable we may get better results. I've seen this error before elsewhere.