split sideWallConnector into parts

rack/side/sideWallMagnetMount.scad

@@ -0,0 +1,16 @@
+
+include <../config.scad>
+include <./sideWallVariables.scad>
+include <../sharedVariables.scad>
+include <../../helper/halfspace.scad>
+include <../../misc/magnet.scad>
+
+module sideWallMagnetMount() {
+  // oriented so that the xy face is the side wall's inner face
+  difference() {
+    cylinder(r1 = magnetMountShellRadius+0.5, r2 = magnetMountShellRadius, h = innerSideWallToYBarMagnetConn);
+
+    translate(v=[0, 0, innerSideWallToYBarMagnetConn-magnetHSlacked])
+    cylinder(r = magnetRSlacked, h = magnetHSlacked);
+  }
+}