Better naming (#2104)

* Move functions from pkg/transport to pkg/parse

Although "parse" is a fairly generic name I believe this is somewhat
better named. pkg/transport keeps a few constants that are uses
throughout for the rest is is renaming a bunch (and the fallout from
there to make things compile again).

Signed-off-by: Miek Gieben <miek@miek.nl>

* Fix tests

Signed-off-by: Miek Gieben <miek@miek.nl>

plugin/proxy/upstream.go

@@ -7,8 +7,8 @@ import (
 	"time"
 
 	"github.com/coredns/coredns/plugin"
-	"github.com/coredns/coredns/plugin/pkg/dnsutil"
 	"github.com/coredns/coredns/plugin/pkg/healthcheck"
+	"github.com/coredns/coredns/plugin/pkg/parse"
 	"github.com/coredns/coredns/plugin/pkg/tls"
 	"github.com/mholt/caddy/caddyfile"
 	"github.com/miekg/dns"
@@ -60,7 +60,7 @@ func NewStaticUpstream(c *caddyfile.Dispenser) (Upstream, error) {
 	}
 
 	// process the host list, substituting in any nameservers in files
-	toHosts, err := dnsutil.ParseHostPortOrFile(to...)
+	toHosts, err := parse.HostPortOrFile(to...)
 	if err != nil {
 		return upstream, err
 	}