add text to share, watch, star, like action

remove wraper of twitter and weibo share button
Edit seed file to style topic page better
redefine avatar size to fit vertical rhythm
Change capybara javascript driver to capybara-webkit
Change is_watching? to watch? to keep consistency

Render both follow and unfollow to keep consistency

Fix bug come from hide!important:

      use toggleClass instead of hide/show
seperate database cleaner settings out
Fix bugs come from edition earlier
Finish topic page craft