Added Lichuan servo motors contributed by Niclas Hedhman.

tests/servo_motors.scad

@@ -0,0 +1,31 @@
+//
+// NopSCADlib Copyright Chris Palmer 2021
+// nop.head@gmail.com
+// hydraraptor.blogspot.com
+//
+// This file is part of NopSCADlib.
+//
+// NopSCADlib is free software: you can redistribute it and/or modify it under the terms of the
+// GNU General Public License as published by the Free Software Foundation, either version 3 of
+// the License, or (at your option) any later version.
+//
+// NopSCADlib is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with NopSCADlib.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+include <../core.scad>
+use <../utils/layout.scad>
+
+include <../vitamins/servo_motors.scad>
+
+module servo_motors()
+    layout([for(s = servo_motors) servo_motor_width(s)], 10) let(s = servo_motors[$i]) {
+        rotate(-90)             // Show the keyway
+            servo_motor(s);
+    }
+
+if($preview)
+    servo_motors();