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/domain_list_test.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestDomainListBasics(t *testing.T) {
+	failTestOnError(t, setupTestEnv())
+
+	domainNew("temp-owner-hex", "Example", "example.com")
+	domainNew("temp-owner-hex", "Example", "example2.com")
+
+	d, err := domainList("temp-owner-hex")
+	if err != nil {
+		t.Errorf("unexpected error listing domains: %v", err)
+		return
+	}
+
+	if len(d) != 2 {
+		t.Errorf("expected number of domains to be 2 got %d", len(d))
+		return
+	}
+
+	if d[0].Domain != "example.com" {
+		t.Errorf("expected first domain to be example.com got %s", d[0].Domain)
+		return
+	}
+
+	if d[1].Domain != "example2.com" {
+		t.Errorf("expected first domain to be example2.com got %s", d[1].Domain)
+		return
+	}
+}