Fix null point exception and rejudge condition in status controller
Merge pull request #172 from mzry1992/fix-issue-170-and-171

Fix null point exception and rejudge condition in status controller
Add export link in contest register page
Add contest registry report exporter
Fix coding style
Merge pull request #173 from mzry1992/contest-registry-report

Contest registry report exporter
Fix bad link in user center
Show team honors in home page
Merge pull request #177 from mzry1992/fix-issue-174

Fix issue 174 and issue 176
update schema of uestcojtest database.
Merge pull request #178 from pfctgeorge/tests

update schema of uestcojtest database.
Update database model
Update contest entity
Request password when contest type is private
Add contest login system
Fix broken test
Merge pull request #179 from mzry1992/contest-permission

Private contest login system
Use view bean to specify view class instead of view name
Merge pull request #180 from mzry1992/contest-permission

Fix strange 404 error in server
remove duplicates in tried problem IDs and accepted problem IDs.