Updated tools version to 2.0.0

Also merged lint-style (gofmt) into golangci-lint (enabled gofmt).
Also removed redundant lint-sanity (govet) which is already checked by golangci-lint.
Also made minor code changes to pass new golangci-lint tests.
Also changed lint-mod slightly so it reverts any changes it makes go.mod, go.sum, and vendor/.

VOL-2647

Change-Id: I2919e65ae29e01c81d1bf7ef113c3189e8227939
diff --git a/internal/pkg/openflow/client.go b/internal/pkg/openflow/client.go
index d921400..4ec41e9 100644
--- a/internal/pkg/openflow/client.go
+++ b/internal/pkg/openflow/client.go
@@ -390,7 +390,7 @@
 	elem := ofp.NewHelloElemVersionbitmap()
 	elem.SetType(ofp.OFPHETVersionbitmap)
 	elem.SetLength(8)
-	elem.SetBitmaps([]*ofp.Uint32{&ofp.Uint32{Value: 16}})
+	elem.SetBitmaps([]*ofp.Uint32{{Value: 16}})
 	hello.SetElements([]ofp.IHelloElem{elem})
 	if logger.V(log.DebugLevel) {
 		js, _ := json.Marshal(hello)