Added Librem5 rough first case design idea

Librem5-Case/librem5-case.scad

+
+// x,y,z dimensions
+// t thickness of frame
+// d screw dome diameter
+// dh screw dome height
+module case_outline(x,y,z,t,d,dh) {
+    union () {
+        difference() {
+            cube ([x, y, z], center=false);
+            translate([t,t,(t/2)]) {
+                cube ([x-2*t, y-2*t, z], center=false);
+            };
+        }
+        translate([d,d,0]) {
+            cylinder (h=dh,r=d,center=false);
+        }
+        translate([x-d,d,0]) {
+            cylinder (h=dh,r=d,center=false);
+        }
+        translate([d,y-d,0]) {
+            cylinder (h=dh,r=d,center=false);
+        }
+        translate([x-d,y-d,0]) {
+            cylinder (h=dh,r=d,center=false);
+        }
+    }
+}
+
+case_outline(72,135,15,1,3,13);
+