remove external connections and core framework diagrams (questionable utility)

Author: wpbonelli

docs/dev/c4.md

@@ -77,71 +77,6 @@ C4Container
   UpdateLayoutConfig($c4ShapeInRow="5", $c4BoundaryInRow="5")
 ```
 
-```mermaid
-C4Container
-  title [Containers] FloPy external connections
-
-  Boundary(flopy, "FloPy"){
-    System(exs, "Examples API")
-    System(gen, "Code generation")
-    System(imp, "Data import")
-    System(exp, "Data export")
-  }
-
-  Boundary(github, "GitHub") {
-    System(mf6, "MODFLOW 6")
-    System(mf6exs, "MODFLOW 6 examples")
-  }
-
-  Boundary(blob, "Storage") {
-    System(aws, "Amazon S3")
-    System(abs, "Azure Blob Storage")
-    System(gcs, "Google Cloud Storage")
-    System(hdfs, "HDFS")
-    System(web, "File server")
-    System(net, "Network file system")
-  }
-
-  Boundary(usgs, "USGS") {
-    System(scibase, "ScienceBase")
-  }
-  
-  Rel(gen, mf6, "retrieves DFNs")
-  Rel(exs, mf6exs, "loads models (e.g. with Pooch)")
-  Rel(imp, aws, "loads data")
-  Rel(imp, abs, "")
-  Rel(imp, gcs, "")
-  Rel(imp, hdfs, "")
-  Rel(imp, web, "")
-  Rel(imp, net, "")
-  Rel(exp, scibase, "loads metadata")
-
-  UpdateRelStyle(gen, mf6, $offsetX="-20")
-```
-
-```mermaid
-C4Component
-  title [Component] FloPy core framework
-
-  Container(fpyprepost, "Pre-/post-processing")
-  Container(fpycodegen, "Code generation")
-  Container(fpymf6, "MF6 Module")
-
-  Container_Boundary(fpycore, "Core framework") {
-    Component(dis, "Discretization")
-    Component(idm, "Input contexts")
-    Component(io, "De/serialization")
-  }
-
-  Rel(fpyprepost, dis, "imports")
-  Rel(fpyprepost, idm, "imports")
-  Rel(fpycodegen, idm, "uses")
-  Rel(fpycodegen, fpymf6, "generates")
-  Rel(fpymf6, dis, "import")
-  Rel(fpymf6, idm, "imports")
-  Rel(fpymf6, io, "imports")
-```
-
 ```mermaid
 C4Component
   title [Component] FloPy code generation