minimagick: mini_magick not working under Windows because of escape chars

Hi, this change (https://github.com/minimagick/minimagick/commit/aeadbed8c04b0f4c5a18c92aa1b6ddb7cdf8d746#commitcomment-2657093) makes mini_magick not working under Windows (7, Ruby 1.9.3, Rails 3.2.11, mini_magick 3.5.0). this is the error: mogrify -resize 800x600> Users/Josef/AppData/Local/Temp/mini_magick20130218-6936-o3gy72.png") failed: {:status_code=>1, :output=>"Magick: invalid argument for option `800x600>

reverting escape_string(value) back to ‘"’ + value + ‘"’ solves the problem…