limit activesupport to < 4 for ruby 1.8
limit activesupport to < 4 for ruby 1.8

moskvax/html-pipeline,gjtorikian/html-pipeline,moskvax/html-pipeline,terracatta/html-pipeline,tricknotes/html-pipeline,jch/html-pipeline,github/html-pipeline,charliesome/html-pipeline,terracatta/html-pipeline,kbrock/html-pipeline,github/html-pipeline,jch/html-pipeline,kbrock/html-pipeline,gjtorikian/html-pipeline