Add "create a page" endpoint

util.go

@@ -0,0 +1,23 @@
+package notion
+
+import "time"
+
+// StringPtr returns the pointer of a string value.
+func StringPtr(s string) *string {
+	return &s
+}
+
+// IntPtr returns the pointer of an int value.
+func IntPtr(i int) *int {
+	return &i
+}
+
+// TimePtr returns the pointer of a time.Time value.
+func BoolPtr(b bool) *bool {
+	return &b
+}
+
+// TimePtr returns the pointer of a time.Time value.
+func TimePtr(t time.Time) *time.Time {
+	return &t
+}