Array#count alias didn't always exist

Fixes mistydemeo/tigerbrew#408.

Library/Homebrew/cmd/list.rb

@@ -100,7 +100,7 @@ module Homebrew
     else # --versions without --pinned
       names.each do |d|
         versions = d.subdirs.map { |pn| pn.basename.to_s }
-        next if ARGV.include?("--multiple") && versions.count < 2
+        next if ARGV.include?("--multiple") && versions.length < 2
         puts "#{d.basename} #{versions*" "}"
       end
     end

Library/Homebrew/patch.rb

@@ -130,7 +130,7 @@ class ExternalPatch
       patch_dir = Pathname.pwd
       if patch_files.empty?
         children = patch_dir.children
-        if (children.count == 1 && children.first.file?)
+        if (children.length == 1 && children.first.file?)
           patch_files << children.first.basename
         else
           raise MissingApplyError, <<-EOS.undent