autoupdate: add optional "--cleanup" flag

Optionally toggle cleaning up automatically after upgrade.

Closes Homebrew#3.

Signed-off-by: Dominyk Tiller <dominyktiller@gmail.com>

README.md

@@ -3,7 +3,7 @@
 An easy, convenient way to automatically update Homebrew.
 
 This script will run once every 24 hours, doing `brew update`.
-`brew upgrade` can also be handled automatically but is an optional flag.
+`brew upgrade` and `brew cleanup` can also be handled automatically but are optional flags.
 
 [![](http://imgs.xkcd.com/comics/update.png)](https://xkcd.com/1328/)
 
@@ -21,6 +21,7 @@ Usage:
 --stop = Stop autoupdating, but retain plist & logs.
 --delete = Cancel the autoupdate, delete the plist and logs.
 --upgrade = Also automatically upgrade your packages.
+--cleanup = Automatically cleanup old packages after upgrade.
 --version = Output this tool's current version.
 ```
 

cmd/brew-autoupdate.rb

@@ -14,18 +14,22 @@ def autoupdate
         --stop = Stop autoupdating, but retain plist & logs.
         --delete = Cancel the autoupdate, delete the plist and logs.
         --upgrade = Also automatically upgrade your packages.
+        --cleanup = Automatically cleanup old packages after upgrade.
         --version = Output this tool's current version.
       EOS
     end
 
     if ARGV.include? "--version"
-      puts "Version 1.1.0, July 2015"
+      puts "Version 1.1.1, February 2016"
     end
 
     if ARGV.include? "--start"
       auto_args = "#{HOMEBREW_PREFIX}/bin/brew update"
       # Spacing at start of line is deliberate. Don't undo.
-      auto_args << " && #{HOMEBREW_PREFIX}/bin/brew upgrade -v" if ARGV.include? "--upgrade"
+      if ARGV.include? "--upgrade"
+        auto_args << " && #{HOMEBREW_PREFIX}/bin/brew upgrade -v"
+        auto_args << " && #{HOMEBREW_PREFIX}/bin/brew cleanup -v" if ARGV.include? "--cleanup"
+      end
 
       file = <<-EOS.undent
         <?xml version="1.0" encoding="UTF-8"?>