Allow multiple arguments to install

Library/Homebrew/extend/pathname.rb

@@ -2,7 +2,8 @@ require 'pathname'
 
 # we enhance pathname to make our code more readable
 class Pathname
-  def install src
+  def install *sources
+    sources.each do |src|
       case src
       when Array
         src.collect {|src| install_p(src) }
@@ -12,6 +13,7 @@ class Pathname
         install_p(src)
       end
     end
+  end
 
   def install_p src, new_basename = nil
     if new_basename