docs(edge): Add @clayms examples

docs/guides/edge.md

@@ -67,3 +67,132 @@ with Diagram(name="Advanced Web Service with On-Premise (colored)", show=False):
 ```
 
 ![advanced web service with on-premise diagram colored](/img/advanced_web_service_with_on-premise_colored.png)
+
+## Less Edges
+
+As you can see on the previous graph the edges can become quickly noisy, here one example to solve this problem.
+
+One hack is to get creative with Custom to create blank placeholders, together with named nodes within Clusters, and then only pointing to single named elements within those Clusters.
+
+Compare the output below to the example output linked to above .
+
+```python
+from diagrams import Cluster, Diagram
+from diagrams.onprem.analytics import Spark
+from diagrams.onprem.compute import Server
+from diagrams.onprem.database import PostgreSQL
+from diagrams.onprem.inmemory import Redis
+from diagrams.onprem.aggregator import Fluentd
+from diagrams.onprem.monitoring import Grafana, Prometheus
+from diagrams.onprem.network import Nginx
+from diagrams.onprem.queue import Kafka
+from diagrams.custom import Custom
+
+with Diagram("\nAdvanced Web Service with On-Premise Less edges", show=False) as diag:
+    ingress = Nginx("ingress")
+
+    with Cluster("Service Cluster"):
+            serv1 = Server("grpc1")
+            serv2 = Server("grpc2")
+            serv3 = Server("grpc3")
+
+    with Cluster(""):
+        blankHA = Custom("","tranparent.png")
+
+        metrics = Prometheus("metric")
+        metrics << Grafana("monitoring")
+
+        aggregator = Fluentd("logging")
+        blankHA >> aggregator >> Kafka("stream") >> Spark("analytics")
+
+        with Cluster("Database HA"):
+            master = PostgreSQL("users")
+            master - PostgreSQL("slave") << metrics
+            blankHA >> master
+
+        with Cluster("Sessions HA"):
+            master = Redis("session")
+            master - Redis("replica") << metrics
+            blankHA >> master
+
+    ingress >> serv2 >> blankHA
+
+diag
+```
+
+![advanced web service with on-premise less edges](/img/advanced_web_service_with_on-premise_less_edges.png)
+
+## Merged Edges
+
+Yet another option is to set the graph_attr dictionary key "concentrate" to "true".
+
+Note the following restrictions:
+
+1.  the Edge must end at the same headport
+2.  this only works when the minlen of the Edges to be greater than "1".
+3.  I could only get this to work when the "splines" graph_attr key was set to the value "spline". It had no effect when the value was set to "ortho", which is the default for the diagrams library.
+4. this will only work with the "dot" layout engine, which is the default for the diagrams library.
+
+For more information see:
+
+  https://graphviz.gitlab.io/doc/info/attrs.html#d:concentrate
+
+  https://www.graphviz.org/pdf/dotguide.pdf Section 3.3 Concentrators
+
+
+
+```python
+from diagrams import Cluster, Diagram, Edge, Node
+from diagrams.onprem.analytics import Spark
+from diagrams.onprem.compute import Server
+from diagrams.onprem.database import PostgreSQL
+from diagrams.onprem.inmemory import Redis
+from diagrams.onprem.aggregator import Fluentd
+from diagrams.onprem.monitoring import Grafana, Prometheus
+from diagrams.onprem.network import Nginx
+from diagrams.onprem.queue import Kafka
+
+graph_attr = {
+    "concentrate": "true",
+    "splines": "spline",
+}
+
+edge_attr = {
+    "minlen":"3",
+}
+
+with Diagram("\n\nAdvanced Web Service with On-Premise Merged edges", show=False,
+            graph_attr=graph_attr,
+            edge_attr=edge_attr) as diag:
+
+    ingress = Nginx("ingress")
+
+    metrics = Prometheus("metric")
+    metrics << Edge(minlen="0") << Grafana("monitoring")
+
+    with Cluster("Service Cluster"):
+        grpsrv = [
+            Server("grpc1"),
+            Server("grpc2"),
+            Server("grpc3")]
+
+    blank = Node("", shape="plaintext", height="0.0", width="0.0")
+
+    with Cluster("Sessions HA"):
+        sess = Redis("session")
+        sess - Redis("replica") << metrics
+
+    with Cluster("Database HA"):
+        db = PostgreSQL("users")
+        db - PostgreSQL("slave") << metrics
+
+    aggregator = Fluentd("logging")
+    aggregator >> Kafka("stream") >> Spark("analytics")
+
+    ingress >> [grpsrv[0], grpsrv[1], grpsrv[2],]
+    [grpsrv[0], grpsrv[1], grpsrv[2],] - Edge(headport="w", minlen="1") - blank
+    blank >> Edge(headport="w", minlen="2") >> [sess, db, aggregator]
+
+diag
+```
+![advanced web service with on-premise merged edges](/img/advanced_web_service_with_on-premise_merged_edges.png)