shows scores only for submitted problems

add feature check maximum score in submission ranges available in the [result] admin menu. A user can enter a range of submissions id and the maximum score per each user,problem among the submission ranges will be reported (grafted from a9d427f3be11871c9948750e94ba5ae988f24eb7)

fixed form_tag bug in views

moved send mail code back to helper

sends mails by mail gem

renamed model Configuration to GraderConfiguration, renamed rhtml views to erb, fixed other small errors

sends mass emails

added default contest

fixed new users import bug when passwords contain extra spaces at the end

shows more login/contest info on result page

also shows users in all (without pagination)

added pagination to user_admin, using will_paginate plugin

assigns all users from on contest list to another

lists users in each contest. individual user contest management moved to each contest user list page

sends notification emails to users after contest upgrade.

a cleaner, testable way to log out user after contest changed

logs out users after contests changed

resets contest start time when changing users' contest

assigns users to a unique contest, small styling on contest title

manages users in contests