Let the gzip utility function accept multiple paths.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

Library/Homebrew/utils.rb

@@ -165,9 +165,11 @@ def exec_editor *args
 end
 
 # GZips the given path, and returns the gzipped file
-def gzip path
-  system "/usr/bin/gzip", path
-  return Pathname.new(path+".gz")
+def gzip *paths
+  paths.collect do |path|
+    system "/usr/bin/gzip", path
+    Pathname.new(path+".gz")
+  end
 end
 
 module ArchitectureListExtension