move graphviz files to graphviz package as Digraphs is extension of that

Author: schnellecom

gap/display.gd

@@ -61,7 +61,7 @@ ReadPackage("digraphs", "gap/labels.gd");
 ReadPackage("digraphs", "gap/attr.gd");
 ReadPackage("digraphs", "gap/prop.gd");
 ReadPackage("digraphs", "gap/oper.gd");
-ReadPackage("digraphs", "gap/display.gd");
+# ReadPackage("digraphs", "gap/display.gd");
 ReadPackage("digraphs", "gap/isomorph.gd");
 ReadPackage("digraphs", "gap/utils.gd");
 ReadPackage("digraphs", "gap/io.gd");

gap/display.gi

@@ -44,7 +44,7 @@ ReadPackage("digraphs", "gap/labels.gi");
 ReadPackage("digraphs", "gap/attr.gi");
 ReadPackage("digraphs", "gap/prop.gi");
 ReadPackage("digraphs", "gap/oper.gi");
-ReadPackage("digraphs", "gap/display.gi");
+# ReadPackage("digraphs", "gap/display.gi");
 ReadPackage("digraphs", "gap/isomorph.gi");
 ReadPackage("digraphs", "gap/io.gi");
 ReadPackage("digraphs", "gap/grahom.gi");