fix whitespace
make stackv4 config slightly easier to read
reverse the ports on stackv4 so http is listening on port 80, and the echo server on 8080
Add DNS example (needs mirage-types 1.1.1 to work)
Merge pull request #30 from avsm/master

tweaks to existing examples
correct listening_port in dns
Add the skeleton for a DNS resolver as well.

This will move into mirage-dns shortly, but it's helpful to write
out the code here first.
fix to dns.0.8.0 api
Merge pull request #31 from avsm/master

Add DNS example (needs mirage-types 1.1.1 to work)