fix typo and indention in spec file
show list of participants avatars
add helper method to return recent participated users
show only 10 recent participated users
link participant avatar to user profile page
show user profile as popover when hover on participant avartar
Prepand hr before participants in event page
Merge branch 'feature/223-participants-list' of git://github.com/doitian/19wu into doitian-feature/223-participants-list
change hr style.

add participants label.
Resize uploaded images
Dispaly image name
Use minimagick instead of rmagick
use zeus to speed up rails. #227
remove jruby head, ruby1.9.2 travis-ci matrix.
Merge pull request #235 from yesmeck/feature/228-resize-image

Resize image
Merge pull request #238 from saberma/saberma-bug/remove-jruby-head-and-ruby-1.9.2-travis-matrix

travis-ci 不要测试  jruby head, ruby1.9.2 环境
Merge pull request #237 from saberma/saberma-enhancement/227-use-zeus-to-speed-rails

使用 zeus 来加速 rails 环境启动