New experimental release available for NetAddr::IP

[Nicholas Bamber <nicholas@periapt.co.uk>]

There is  a new experimental release with all the #601601 patches I 
could find. I'm leaving the patch for #517361 as I hope to show that 
they are at least harmless, they have been sent upstream and they look 
right to me. Also this the experimental so there is no shame in 
unpicking one of the patches later if necessary.