title: On composer install error throws up saying I don't have Mcrypt PHP
body: <p>When I do <code>composer install</code> on my homestead set up for a VM using laravel (on mac OSX Yosemite) I get the following error:</p>
  
  <pre><code>$ composer install
  Warning: This development build of composer is over 30 days old. It is 
  recommended to update it by running "/usr/local/bin/composer self-update" to get the 
  latest version.
  Loading composer repositories with package information
  Installing dependencies (including require-dev) from lock file
  Nothing to install or update
  Generating autoload files
  Mcrypt PHP extension required.
  Script php artisan clear-compiled handling the post-install-cmd event returned 
  with an error
  
    [RuntimeException]  
    Error Output:       
  
  install [--prefer-source] [--prefer-dist] [--dry-run] 
  [--dev] [--no-dev] [--no-plugins] [--no-custom-installers] [--no-autoloader] 
  [--no-scripts] [--no-progress] [-v|vv|vvv|--verbose] [-o|--optimize-autoloader]
  [--ignore-platform-reqs] [packages1] ... [packagesN]
  </code></pre>
  
  <p>When I then run the command <code>$ brew install php5-mcrypt</code>. I get the following:</p>
  
  <pre><code>$ brew install php5-mcrypt
  Error: No available formula for php5-mcrypt 
  Searching formulae...
  Searching taps...
  $
  </code></pre>
  
  <p>How do I fix this and get php5-mcrypt installed?</p>