Bug#1088264: tayga: Tayga does not forward UDPv4 packets with zero checksums

[Mark Glines]

Note, the new upstream fork (see #1107302) has a fix for this:
https://github.com/apalrd/tayga/pull/76

They make the behavior configurable, and it looks like the "calc" option 
covers my use-case.

Thanks,

Mark