show 'create new topic' button on homepage
upgrade to Rails 3.2.14
create topic from homepage
Merge branch 'new-topic-button-homepage' into 1.5-stable
node_id should be protected
add background image
Revert "add background image"

This reverts commit 20700005ab2c588cafa21566efb461ab7a2b99e0.
fix external img style bug
Merge branch 'master' into 1.5-stable
update ruby version
install ruby 2.0.0-p247 for auto deploy on ubuntu
Merge branch '1.5-stable'