title: jshint --version command not be found by proc_open
body: <p>I have been figuring out the installation of archanist with linters on my Windows 8.2 (64 bit) system. I ran into problem during <code>arc diff</code>, when it said (over git bash, I was using):</p>
  
  <pre><code>EXCEPTION: (PhutilAggregateException) Some linters failed:
      - ArcanistMissingLinterException: Unable to locate binary "jshint" to run linter ArcanistJSHintLinter. You may need to install the binary, or adjust your linter configuration.
        TO INSTALL: Install JSHint using `npm install -g jshint`. at [&lt;arcanist&gt;\src\lint\engine\ArcanistLintEngine.php:264]
  </code></pre>
  
  <p>Then I tried install jshint through </p>
  
  <pre><code>npm install -g jshint
  </code></pre>
  
  <p>Then, a new error occurred, where it tries to execute the command jshint --version, then the error log was:</p>
  
  <pre><code>[2020-06-01 20:14:22] EXCEPTION: (CommandException) Command failed with error #1!
  COMMAND
  jshint --version
  
  STDOUT
  (empty)
  
  STDERR
  Call to "proc_open()" to open a subprocess failed: proc_open(): CreateProcess failed, error code - 2 at [&lt;arcanist&gt;\src\future\exec\ExecFuture.php:409]
  arcanist(head=master, ref.master=0da1a2e17d92)
    #0 ExecFuture::raiseResultError(array) called at [&lt;arcanist&gt;\src\future\exec\ExecFuture.php:313]
  </code></pre>
  
  <p>I then debugged it further, it uses proc_open method to execute the command, which returns bool(false). Even though I tried to run via shell:</p>
  
  <pre><code>jshint --version
  </code></pre>
  
  <p>It outputted: jshint v2.11.1</p>
  
  <p>But same if proc_open does, it returned false.</p>
  
  <p><strong>php version : 5.4.9</strong> </p>
  
  <p><strong>arc version : arcanist 0da1a2e17d921dc27ce9afa76b123cb4c8b73b17 (30 May 2020)</strong></p>
  
  <p>My .arclint file contains this:</p>
  
  <pre><code>{
      "linters":{
         "jshint":{
             "type":"jshint",
             "include":"(\\.js$)"
         },
         "php":{
              "type":"php",
              "include":"(\\.php$)"
           }
      }
  }
  </code></pre>