cmd/go: update go help mod edit with the tool and ignore sections

The types were added to the docs, but not the fields in GoMod.
While here, I was initially confused about what is the top-level type
given that `type Module` comes first. Move `type GoMod` to the top
as it is the actual top-level type.

Change-Id: I1270154837501f5c7f5b21959b2841fd4ac808d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/700116
Reviewed-by: Sean Liao <sean@liao.dev>
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Junyang Shao <shaojunyang@google.com>

src/cmd/go/alldocs.go

@@ -1280,11 +1280,6 @@
 // The -json flag prints the final go.mod file in JSON format instead of
 // writing it back to go.mod. The JSON output corresponds to these Go types:
 //
-//	type Module struct {
-//		Path    string
-//		Version string
-//	}
-//
 //	type GoMod struct {
 //		Module    ModPath
 //		Go        string
@@ -1294,6 +1289,13 @@
 //		Exclude   []Module
 //		Replace   []Replace
 //		Retract   []Retract
+//		Tool      []Tool
+//		Ignore    []Ignore
+//	}
+//
+//	type Module struct {
+//		Path    string
+//		Version string
 //	}
 //
 //	type ModPath struct {

src/cmd/go/internal/modcmd/edit.go

@@ -104,11 +104,6 @@ writing it back to go.mod.
 The -json flag prints the final go.mod file in JSON format instead of
 writing it back to go.mod. The JSON output corresponds to these Go types:
 
-	type Module struct {
-		Path    string
-		Version string
-	}
-
 	type GoMod struct {
 		Module    ModPath
 		Go        string
@@ -118,6 +113,13 @@ writing it back to go.mod. The JSON output corresponds to these Go types:
 		Exclude   []Module
 		Replace   []Replace
 		Retract   []Retract
+		Tool      []Tool
+		Ignore    []Ignore
+	}
+
+	type Module struct {
+		Path    string
+		Version string
 	}
 
 	type ModPath struct {