Add debug button to change admin and contestant

This commit will be reverted
Default user is not admin
Fix spec helpers
refs #71
Fix specs for #71
Add depedency of capybara
Modify seed to create numbered groups with argument
Add usage of `rake db:seed groups=N`
Merge pull request #121 from TakenokoChocoHolic/120_numbered_group_seed

120 numbered group seed
Add spec for acceptance testing with Capybara.
Update .gitignore
Fix ScoresHelper
Merge pull request #119 from murooka/restrict_admin_page

Restrict admin page
Merge pull request #123 from TakenokoChocoHolic/capybara

Add acceptance tests using Capybara