add node modules to repo

app/node_modules/fs-extra/lib/ensure/link.js

@@ -0,0 +1,58 @@
+var path = require('path')
+var fs = require('graceful-fs')
+var mkdir = require('../mkdirs')
+
+function createLink (srcpath, dstpath, callback) {
+  function makeLink (srcpath, dstpath) {
+    fs.link(srcpath, dstpath, function (err) {
+      if (err) return callback(err)
+      callback(null)
+    })
+  }
+
+  fs.exists(dstpath, function (destinationExists) {
+    if (destinationExists) return callback(null)
+    fs.lstat(srcpath, function (err, stat) {
+      if (err) {
+        err.message = err.message.replace('lstat', 'ensureLink')
+        return callback(err)
+      }
+
+      var dir = path.dirname(dstpath)
+      fs.exists(dir, function (dirExists) {
+        if (dirExists) return makeLink(srcpath, dstpath)
+        mkdir.mkdirs(dir, function (err) {
+          if (err) return callback(err)
+          makeLink(srcpath, dstpath)
+        })
+      })
+    })
+  })
+}
+
+function createLinkSync (srcpath, dstpath, callback) {
+  var destinationExists = fs.existsSync(dstpath)
+  if (destinationExists) return undefined
+
+  try {
+    fs.lstatSync(srcpath)
+  } catch (err) {
+    err.message = err.message.replace('lstat', 'ensureLink')
+    throw err
+  }
+
+  var dir = path.dirname(dstpath)
+  var dirExists = fs.existsSync(dir)
+  if (dirExists) return fs.linkSync(srcpath, dstpath)
+  mkdir.mkdirsSync(dir)
+
+  return fs.linkSync(srcpath, dstpath)
+}
+
+module.exports = {
+  createLink: createLink,
+  createLinkSync: createLinkSync,
+  // alias
+  ensureLink: createLink,
+  ensureLinkSync: createLinkSync
+}