update README doc. diagrams.

I added a .dot file for the Return to Riterdon project overview and
fix the image links for so the diagrams sit in their correct places
within the document.

README.md

@@ -89,5 +89,5 @@ You can read the documentation in this repository in two ways:
 
 1. read the raw markdown (.md) files within the project folders in
   this repository, or;
-~~2. download a 'Released' version and read that (as a .pdf).~~
+2. ~~download a 'Released' version and read that (as a .pdf).~~
 

attachments/main-proj-architecture.dot

@@ -1,30 +1,14 @@
 digraph overview {
-	fontname = Arial;
 	node [fontname = Arial];
-	label = "Return to Ritherdon";
-	labelloc = top;
-	style = filled;
-	color = lightgrey;
-	fontsize = 20;
-	subgraph cluster0 {
-		style = filled;
-		node [style = filled, color = white];
-		color = lightblue;
-		label = "Personal Flash in Real-Time (I.E. 'Artwork 1')";
-		fontsize = 16;
-		Light;
-		Midpoint;
-		Relay;
-	}
-	subgraph cluster1 {
-		label = "The other artworks in the exhibiton/project...";
-		fontsize = 16;
-		color = white;
-		style = filled;
-		a5 [label = "Artwork 5"];		
-		a4 [label = "Artwork 4"];
-		a3 [label = "Artwork 3"];
-		a2 [label = "Artwork 2"];
-	}
+	l1 -> server;
+	l2 -> server;
+	server -> r1;
+	server -> r2;
+	r1 -> server;
+	r2 -> server;
+	l1 [label = "Light Meter 1", color = lightblue, style = filled];
+	l2 [label = "Light Meter 2", color = orange, style = filled];
+	r1 [label = "Relay 1", color = lightblue, style = filled];
+	r2 [label = "Relay 2", color = orange, style = filled ];
+	server [label = "Midpoint (Server)"];
 }
-