major interface conversion update

- module instances with modport bindings are now inlined
- support for modports in generate loops
- support for generic interfaces
- implied modport instance propagation
- add error message for interface instances missing port list

test/basic/interface_module.v

@@ -0,0 +1,12 @@
+module ModuleC;
+    wire y;
+    assign y = 1;
+    initial $display("ModuleB %b", y);
+    wire x;
+    assign x = 0;
+    initial $display("ModuleA %b", x);
+endmodule
+
+module top;
+    ModuleC module_c();
+endmodule