Remove the word middleware (#1067)

* Rename middleware to plugin

first pass; mostly used 'sed', few spots where I manually changed
text.

This still builds a coredns binary.

* fmt error

* Rename AddMiddleware to AddPlugin

* Readd AddMiddleware to remain backwards compat

1 files changed, 0 insertions, 24 deletions

diff --git a/middleware/file/closest.go b/middleware/file/closest.go
deleted file mode 100644
index ea201671f..000000000
--- a/middleware/file/closest.go
+++ /dev/null
@@ -1,24 +0,0 @@
-package file
-
-import (
-	"github.com/coredns/coredns/middleware/file/tree"
-
-	"github.com/miekg/dns"
-)
-
-// ClosestEncloser returns the closest encloser for qname.
-func (z *Zone) ClosestEncloser(qname string) (*tree.Elem, bool) {
-
-	offset, end := dns.NextLabel(qname, 0)
-	for !end {
-		elem, _ := z.Tree.Search(qname)
-		if elem != nil {
-			return elem, true
-		}
-		qname = qname[offset:]
-
-		offset, end = dns.NextLabel(qname, offset)
-	}
-
-	return z.Tree.Search(z.origin)
-}