Pull request: all: get rid of labels

Merge in DNS/adguard-home from rm-labels to master

Squashed commit of the following:

commit 5e3688ed92b0f76a47078a55bc22c401422c914c
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Thu Dec 9 17:46:50 2021 +0300

    all: imp code, docs

commit 123d1ec52d0037315e8de94ab5a26b48cf0bf984
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Thu Dec 9 17:14:05 2021 +0300

    all: get rid of labels

internal/aghnet/hostscontainer.go

@@ -309,21 +309,22 @@ func (hp *hostsParser) parseLine(line string) (ip net.IP, hosts []string) {
 		return nil, nil
 	}
 
-loop:
 	for _, f := range fields[1:] {
 		switch hashIdx := strings.IndexByte(f, '#'); hashIdx {
-		case 0:
-			// The rest of the fields are a part of the comment so skip
-			// immediately.
-			break loop
 		case -1:
 			hosts = append(hosts, f)
+
+			continue
+		case 0:
+			// Go on.
 		default:
 			// Only a part of the field is a comment.
 			hosts = append(hosts, f[:hashIdx])
-
-			break loop
 		}
+
+		// The rest of the fields are a part of the comment so skip
+		// immediately.
+		break
 	}
 
 	return ip, hosts