title: Couldn't find the 'yo' binary. Make sure it's installed and in your $PATH. Could you tell me what the problem is?
body: <pre><code>I'm using npm install -g yo gulp to install yeoman and this is the error I'm getting  
  npm WARN deprecated cross-spawn-async@2.2.5: cross-spawn no longer requires a build toolchain, use it instead
  C:\Usr\local\gulp -&gt; C:\Usr\local\node_modules\gulp\bin\gulp.js
  C:\Usr\local\yo -&gt; C:\Usr\local\node_modules\yo\lib\cli.js
  C:\Usr\local\yo-complete -&gt; C:\Usr\local\node_modules\yo\lib\completion\index.js
  
  &gt; yo@3.1.0 postinstall C:\Usr\local\node_modules\yo
  &gt; yodoctor
  
  
  Yeoman Doctor
  Running sanity checks on your system
  
  √ No .bowerrc file in home directory
  √ Global configuration file is valid
  √ NODE_PATH matches the npm root
  √ No .yo-rc.json file in home directory
  √ Node.js version
  { Error: Couldn't find the 'yo' binary. Make sure it's installed and in your $PATH
      at notFoundError (C:\Usr\local\node_modules\yo\node_modules\cross-spawn-async\lib\enoent.js:8:11)
      at verifyENOENT (C:\Usr\local\node_modules\yo\node_modules\cross-spawn-async\lib\enoent.js:43:16)
      at ChildProcess.cp.emit (C:\Usr\local\node_modules\yo\node_modules\cross-spawn-async\lib\enoent.js:30:19)
      at Process.ChildProcess._handle.onexit (internal/child_process.js:198:12)
    errno: 'ENOENT',
    code: 'ENOENT',
    syscall: 'spawn yo',
    cmd: 'C:\\WINDOWS\\system32\\cmd.exe /s /c "yo "--version""' }
  × yo version
  { Error: Couldn't find the 'yo' binary. Make sure it's installed and in your $PATH
      at notFoundError (C:\Usr\local\node_modules\yo\node_modules\cross-spawn-async\lib\enoent.js:8:11)
      at verifyENOENT (C:\Usr\local\node_modules\yo\node_modules\cross-spawn-async\lib\enoent.js:43:16)
      at ChildProcess.cp.emit (C:\Usr\local\node_modules\yo\node_modules\cross-spawn-async\lib\enoent.js:30:19)
      at Process.ChildProcess._handle.onexit (internal/child_process.js:198:12)
    errno: 'ENOENT',
    code: 'ENOENT',
    syscall: 'spawn yo',
    cmd: 'C:\\WINDOWS\\system32\\cmd.exe /s /c "yo "--version""' }
  √ npm version
  
  Found potential issues on your machine :(
  npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.9 (node_modules\gulp\node_modules\fsevents):
  npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.9: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})
  
  + gulp@4.0.2
  + yo@3.1.0
  updated 2 packages in 23.31s
  </code></pre>