add listAllColours function to lib and rename applyGrid to async.

DeathSocket/GridPainter.fs

@@ -6,12 +6,22 @@ namespace DeathSocket
 
         open Validation
         open ImageServices
+        open System.Drawing
+        open System.Reflection
 
-        let applyGrid spec =
+        let applyGridAsync spec =
             async {
                 try
                     validateFilePath |> ignore
                     drawGrid spec |> ignore
                 with
-                | :? FileNotFoundException as ex -> printfn "File could not be found at %s" ex.Message
-            }
+                | :? FileNotFoundException as ex ->
+                    printfn "File could not be found at %s" ex.Message
+            }
+
+        let ListAllColours =
+            let properties =
+                typeof<Brushes>.GetProperties
+                    (BindingFlags.Public ||| BindingFlags.Static)
+            seq { for prop in properties -> prop }
+            |> Seq.toList