Update dependencies to napi versions to support Node 12

appveyor.yml

@@ -1,13 +1,13 @@
 # Test against this version of Node.js
 environment:
-  nodejs_version: "4.1.2"
+  nodejs_version: "12.13.1"
 
 # Install scripts. (runs after repo cloning)
 install:
   # Get the latest stable version of Node.js or io.js
   - ps: Install-Product node $env:nodejs_version
   # Upgrade npm
-  - npm install -g npm@3
+  - npm install -g npm@6
   # install modules
   - npm install
   - npm install grunt-cli -g

lib/native/adv_api.js

@@ -1,7 +1,7 @@
 // Minimal wrappers for Advapi32.dll to support basic registry manipulations
 
 'use strict';
-var ffi = require('ffi'),
+var ffi = require('ffi-napi'),
     types = require('../types');
 
 // Javascript bindings for native Win32 registry APIs

lib/native/shell32.js

@@ -1,7 +1,7 @@
 // Minimnal wrappers for shell32.js
 var windef = require('../windef'),
-    ffi = require('ffi'),
-    ref = require('ref');
+    ffi = require('ffi-napi'),
+    ref = require('ref-napi');
 
 var SHELLEXECUTEINFOPtr = ref.refType(windef.SHELLEXECUTEINFO);
 var shell32 = new ffi.Library('Shell32', {

lib/registry.js

@@ -1,10 +1,10 @@
 /* global Buffer */
 'use strict';
-var ffi = require('ffi'),
+var ffi = require('ffi-napi'),
     types = require('./types'),
     advApi = require('./native/adv_api'),
     Key = require('./key'),
-    ref = require('ref'),
+    ref = require('ref-napi'),
     error = require('./error'),
     windef = require('./windef'),
     debug = require('debug')('windows-registry');

lib/types.js

@@ -1,4 +1,4 @@
-var ref = require('ref');
+var ref = require('ref-napi');
 
 var types = {
     REGSAM: ref.types.ulong,

lib/utils.js

@@ -1,5 +1,5 @@
 'use strict';
-var ref = require('ref'),
+var ref = require('ref-napi'),
     types = require('./types'),
     shell32 = require('./native/shell32'),
     windef = require('./windef'),

lib/windef.js

@@ -1,6 +1,7 @@
+var ref = require('ref-napi');
 var types = require('./types'),
-    struct = require('ref-struct'),
-    uniontype = require('ref-union');
+    struct = require('ref-struct-napi'),
+    uniontype = require('ref-union-di')(ref);
 
 // yes, this is the name in the official MSDN doc
 var DUMMYUNIONNAME = uniontype({