Add support to build node.js with chakracore.

Microsoft's chakracore engine is dependent on Windows SDK, and build
tools should know the version installed on user machine. This change
adds those dependencies in node-gyp tools. Below is the summary:

* Configure msvs_windows_target_platform_version to use the right
  Windows SDK.

* Configure msvs_use_library_dependency_inputs to export symbols
  correctly (otherwise functions not used by node.exe but might be
  needed by native addon modules could be optimized away by linker).

These changes were originally made in nodejs/node#4765, but as @shigeki
mentioned, it was more sensible to send these changes as PR to node-gyp
repo.

PR-URL: https://github.com/nodejs/node-gyp/pull/873
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

addon.gypi

@@ -1,14 +1,25 @@
 {
+  'variables' : {
+    'node_engine_include_dir%': 'deps/v8/include',
+  },
   'target_defaults': {
     'type': 'loadable_module',
     'win_delay_load_hook': 'true',
     'product_prefix': '',
 
+    'conditions': [
+      [ 'node_engine=="chakracore"', {
+        'variables': {
+          'node_engine_include_dir%': 'deps/chakrashim/include'
+        },
+      }]
+    ],
+
     'include_dirs': [
       '<(node_root_dir)/include/node',
       '<(node_root_dir)/src',
       '<(node_root_dir)/deps/uv/include',
-      '<(node_root_dir)/deps/v8/include'
+      '<(node_root_dir)/<(node_engine_include_dir)'
     ],
     'defines!': [
       'BUILDING_UV_SHARED=1',  # Inherited from common.gypi.
@@ -79,6 +90,12 @@
         ],
       }],
       [ 'OS=="win"', {
+        'conditions': [
+          ['node_engine=="chakracore"', {
+            'library_dirs': [ '<(node_root_dir)/$(ConfigurationName)' ],
+            'libraries': [ '<@(node_engine_libs)' ],
+          }],
+        ],
         'libraries': [
           '-lkernel32.lib',
           '-luser32.lib',