ensure hosts are set when building

otherwise when we try to add the certs to .gnutls/known_hosts, it wont
get the correct cert

build.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+export IP=$(getent ahostsv4 freegamez.ga | awk '{ print $1 }' | head -1)
+
+docker build -t taylorbourne/xteve_lazystream \
+	--add-host="mf.svc.nhl.com:$IP" \
+	--add-host="playback.svcs.mlb.com:$IP" \
+	--add-host="mlb-ws-mf.media.mlb.com:$IP" \
+	.