rename connectingBar to yBar, and add mockup of new xBar. Also mess around with the full assembly

helper/cylindricalFilet.scad

@@ -0,0 +1,16 @@
+
+module cylindricalFiletEdge(width, depth, height, roundness) {
+  rd = roundness;
+
+  intersection() {
+    minkowski() {
+      rotate(a = [90, 0, 0])
+      cylinder(r = rd, h = eps);
+
+      translate(v = [rd, 0, rd])
+      cube(size = [width, depth, height]);
+    }
+
+    cube(size = [width, depth, height]);
+  }
+}