add support for node v7

node version 7 officially deprecates `fs.read` and `fs.readSync`

This is done using `internal/util`. The unfortunate side affect
being that `graceful-fs v3.x` explodes when running the code in
`vm` as `internal/util` is not accessible from userland.

This commit uses a regular expression to replaces the require of
the specific internal util function with the source of that util
function. As such `graceful-fs v3.x` will no longer explode in
node v7.

One advantage to this approach is that any future deprecation
will not break graceful-fs.

fs.js

@@ -6,6 +6,27 @@ var mod = require("module")
 var pre = '(function (exports, require, module, __filename, __dirname) { '
 var post = '});'
 var src = pre + process.binding('natives').fs + post
+var deprecation = ''
+
+var printDeprecation = ['var prefix = \'(\' + [process.release.name, process.pid].join(\':\') + \')\';',
+'var printDeprecation = function(msg, warned) {',
+'  if (process.noDeprecation)',
+'    return true;',
+'  if (warned)',
+'    return warned;',
+'  if (process.throwDeprecation)',
+'    throw new Error(prefix + msg);',
+'  else if (process.traceDeprecation)',
+'    console.trace(msg);',
+'  else',
+'    console.error(prefix + msg);',
+'  return true;',
+'};'].join('\n');
+
+var deprecrationRequire = /const printDeprecation = require\(\'internal\/util\'\).printDeprecationMessage;/
+
+src = src.replace(deprecrationRequire, printDeprecation);
+
 var vm = require('vm')
 var fn = vm.runInThisContext(src)
 fn(exports, require, module, __filename, __dirname)