add registration form in the new_user_session view
Merge branch 'issues_187_add_registration_form' of git://github.com/ywjno/19wu into ywjno-issues_187_add_registration_form
after user sign in, redirect to previous page. close #187

add standalone registration page.
Merge branch 'master' of github.com:saberma/19wu
change register button color in user bar.
delete one resources because they're not need
Merge pull request #218 from ywjno/delete_not_need_resources

delete not need resources
extract out has_html_pipeline as gem

See https://github.com/doitian/has_html_pipeline
Merge pull request #220 from doitian/bug/183-html-pipeline-init

extract out has_html_pipeline as gem
update homepage style.
Merge pull request #221 from saberma/saberma-enhancement/update-homepage-style

调整首页样式.