Remove zshrc post-install inserts

Rakefile

@@ -321,18 +321,6 @@ def install_files(files, method = :symlink)
       run %{ cp -f "#{source}" "#{target}" }
     end
 
-    # Temporary solution until we find a way to allow customization
-    # This modifies zshrc to load all of yadr's zsh extensions.
-    # Eventually yadr's zsh extensions should be ported to prezto modules.
-    source_config_code = "for config_file ($HOME/.yadr/zsh/*.zsh) source $config_file"
-    if file == 'zshrc'
-      File.open(target, 'a+') do |zshrc|
-        if zshrc.readlines.grep(/#{Regexp.escape(source_config_code)}/).empty?
-          zshrc.puts(source_config_code)
-        end
-      end
-    end
-
     puts "=========================================================="
     puts
   end