vulkan: update to header 1.0.42

Updated all necessary files to 1.0.42.  This includes the various
headers as well as the loader, and the parameter validation, object
tracking, and threading layers.  Additionally, bump all layer JSON
files to 1.0.42.

Also, in this change:
  - Enable loader extension automation so that the loader now
    generates all extension entry-points automatically during build
    to reduce likelihood of missing a critical piece on header
    update.
  - Enable layer dispatch table extension automation for the same
    reason.
  - Fixes from Mark Lobodzinski and Tony Barbour to resolve crash
    in loader when working with Intel's Windows driver due to
    GetInstanceProcAddr getting called on inappropriate command
    names.

Change-Id: Ic18d3fac2e145c386c0192031deb5089c91a00d8
diff --git a/scripts/lvl_genvk.py b/scripts/lvl_genvk.py
index 0be5d3e..0789b66 100644
--- a/scripts/lvl_genvk.py
+++ b/scripts/lvl_genvk.py
@@ -22,8 +22,9 @@
 from threading_generator import  ThreadGeneratorOptions, ThreadOutputGenerator
 from parameter_validation_generator import ParamCheckerGeneratorOptions, ParamCheckerOutputGenerator
 from unique_objects_generator import UniqueObjectsGeneratorOptions, UniqueObjectsOutputGenerator
-from dispatch_table_generator import DispatchTableOutputGenerator, DispatchTableOutputGeneratorOptions
+from dispatch_table_helper_generator import DispatchTableHelperOutputGenerator, DispatchTableHelperOutputGeneratorOptions
 from helper_file_generator import HelperFileOutputGenerator, HelperFileOutputGeneratorOptions
+from loader_extension_generator import LoaderExtensionOutputGenerator, LoaderExtensionGeneratorOptions
 
 # Simple timer functions
 startTime = None
@@ -162,11 +163,10 @@
             alignFuncParam    = 48)
         ]
 
-
     # Options for dispatch table helper generator
     genOpts['vk_dispatch_table_helper.h'] = [
-          DispatchTableOutputGenerator,
-          DispatchTableOutputGeneratorOptions(
+          DispatchTableHelperOutputGenerator,
+          DispatchTableHelperOutputGeneratorOptions(
             filename          = 'vk_dispatch_table_helper.h',
             directory         = directory,
             apiname           = 'vulkan',
@@ -184,6 +184,69 @@
             alignFuncParam    = 48)
         ]
 
+    # Options for Layer dispatch table generator
+    genOpts['vk_layer_dispatch_table.h'] = [
+          LoaderExtensionOutputGenerator,
+          LoaderExtensionGeneratorOptions(
+            filename          = 'vk_layer_dispatch_table.h',
+            directory         = directory,
+            apiname           = 'vulkan',
+            profile           = None,
+            versions          = allVersions,
+            emitversions      = allVersions,
+            defaultExtensions = 'vulkan',
+            addExtensions     = addExtensions,
+            removeExtensions  = removeExtensions,
+            prefixText        = prefixStrings + vkPrefixStrings,
+            protectFeature    = False,
+            apicall           = 'VKAPI_ATTR ',
+            apientry          = 'VKAPI_CALL ',
+            apientryp         = 'VKAPI_PTR *',
+            alignFuncParam    = 48)
+        ]
+
+    # Options for loader extension source generator
+    genOpts['vk_loader_extensions.h'] = [
+          LoaderExtensionOutputGenerator,
+          LoaderExtensionGeneratorOptions(
+            filename          = 'vk_loader_extensions.h',
+            directory         = directory,
+            apiname           = 'vulkan',
+            profile           = None,
+            versions          = allVersions,
+            emitversions      = allVersions,
+            defaultExtensions = 'vulkan',
+            addExtensions     = addExtensions,
+            removeExtensions  = removeExtensions,
+            prefixText        = prefixStrings + vkPrefixStrings,
+            protectFeature    = False,
+            apicall           = 'VKAPI_ATTR ',
+            apientry          = 'VKAPI_CALL ',
+            apientryp         = 'VKAPI_PTR *',
+            alignFuncParam    = 48)
+        ]
+
+    # Options for loader extension source generator
+    genOpts['vk_loader_extensions.c'] = [
+          LoaderExtensionOutputGenerator,
+          LoaderExtensionGeneratorOptions(
+            filename          = 'vk_loader_extensions.c',
+            directory         = directory,
+            apiname           = 'vulkan',
+            profile           = None,
+            versions          = allVersions,
+            emitversions      = allVersions,
+            defaultExtensions = 'vulkan',
+            addExtensions     = addExtensions,
+            removeExtensions  = removeExtensions,
+            prefixText        = prefixStrings + vkPrefixStrings,
+            protectFeature    = False,
+            apicall           = 'VKAPI_ATTR ',
+            apientry          = 'VKAPI_CALL ',
+            apientryp         = 'VKAPI_PTR *',
+            alignFuncParam    = 48)
+        ]
+
     # Helper file generator options for vk_enum_string_helper.h
     genOpts['vk_enum_string_helper.h'] = [
           HelperFileOutputGenerator,