api: Add go files

I know this is a huge commit, but I can't be bothered to check
this in part by part.

api/comment_ownership_verify_test.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"testing"
+	"time"
+)
+
+func TestCommentOwnershipVerifyBasics(t *testing.T) {
+	failTestOnError(t, setupTestEnv())
+
+	commentHex, _ := commentNew("temp-commenter-hex", "example.com", "/path.html", "root", "**foo**", "approved", time.Now().UTC())
+
+	isOwner, err := commentOwnershipVerify("temp-commenter-hex", commentHex)
+	if err != nil {
+		t.Errorf("unexpected error verifying ownership: %v", err)
+		return
+	}
+
+	if !isOwner {
+		t.Errorf("expected to be owner of comment")
+		return
+	}
+
+	isOwner, err = commentOwnershipVerify("another-commenter-hex", commentHex)
+	if err != nil {
+		t.Errorf("unexpected error verifying ownership: %v", err)
+		return
+	}
+
+	if isOwner {
+		t.Errorf("unexpected owner of comment not created by another-commenter-hex")
+		return
+	}
+}
+
+func TestCommentOwnershipVerifyEmpty(t *testing.T) {
+	failTestOnError(t, setupTestEnv())
+
+	if _, err := commentOwnershipVerify("temp-commenter-hex", ""); err == nil {
+		t.Errorf("expected error not founding verifying ownership with empty commentHex")
+		return
+	}
+}