extensions: begin changes for extension support

This patch starts restructuring the various components
(loader, driver, layers, etc.) to support global and
device extensions. Require GetProcAddr to access the
extension functions and related support.
diff --git a/tests/render_tests.cpp b/tests/render_tests.cpp
index 95fdfd6..df9c5a0 100644
--- a/tests/render_tests.cpp
+++ b/tests/render_tests.cpp
@@ -68,7 +68,7 @@
 #include "../layers/object_track.h"
 #endif
 #ifdef DEBUG_CALLBACK
-#include <vkDbg.h>
+#include <vk_debug_report_lunarg.h>
 #endif
 #include "gtest-1.7.0/include/gtest/gtest.h"
 
@@ -94,7 +94,7 @@
         case VK_DBG_MSG_WARNING:
             printf("CALLBACK WARNING : %s\n", pMsg);
             break;
-        case VK_DBG_MSG_ERROR:
+        case VK_DBG_REPORT_ERROR_BIT:
             printf("CALLBACK ERROR : %s\n", pMsg);
             break;
         default:
@@ -498,7 +498,7 @@
     OBJTRACK_NODE* pObjNodeArray = (OBJTRACK_NODE*)malloc(sizeof(OBJTRACK_NODE)*numObjects);
     pObjTrackGetObjs(numObjects, pObjNodeArray);
     for (i=0; i < numObjects; i++) {
-        printf("Object %i of type %s has objID (%p) and %lu uses\n", i, string_from_vulkan_object_type(pObjNodeArray[i].objType), pObjNodeArray[i].vkObj, pObjNodeArray[i].numUses);
+        printf("Object %i of type %s has objID (%p) and %lu uses\n", i, string_VkObjectType(pObjNodeArray[i].objType), pObjNodeArray[i].pObj, pObjNodeArray[i].numUses);
     }
     free(pObjNodeArray);
 #endif