util to help diagnose egress interface identification problems

[pgalbraith]

No description provided.

[cowtowncoder]

@pgalbraith I was able to run this, getting output like so:

{java.runtime.name=OpenJDK Runtime Environment, sun.boot.library.path=/Library/Java/JavaVirtualMachines/adoptopenjdk-8.jdk/Contents/Home/jre/lib, java.vm.version=25.272-b10,  ... lots of values, not included here yet ...

remote: a.root-servers.net/198.41.0.4:0
local: 0.0.0.0/0.0.0.0
interface: null
java.lang.NullPointerException
java.lang.NullPointerException
	at test.EgressDiagnostics.tryRemote(EgressDiagnostics.java:24)
	at test.EgressDiagnostics.main(EgressDiagnostics.java:8)

remote: a.root-servers.net/198.41.0.4:53
local: 0.0.0.0/0.0.0.0
interface: null
java.lang.NullPointerException
java.lang.NullPointerException
	at test.EgressDiagnostics.tryRemote(EgressDiagnostics.java:24)
	at test.EgressDiagnostics.main(EgressDiagnostics.java:9)

remote: /1.1.1.1:0
local: 0.0.0.0/0.0.0.0
interface: null
java.lang.NullPointerException
java.lang.NullPointerException
	at test.EgressDiagnostics.tryRemote(EgressDiagnostics.java:24)
	at test.EgressDiagnostics.main(EgressDiagnostics.java:10)

remote: /1:0:0:0:0:0:0:1:0
local: 0.0.0.0/0.0.0.0
interface: null
java.lang.NullPointerException
java.lang.NullPointerException
	at test.EgressDiagnostics.tryRemote(EgressDiagnostics.java:24)
	at test.EgressDiagnostics.main(EgressDiagnostics.java:11)