timezone string limited to 20 char whereas some timezones are greater than 20

Review Request #4230 — Created June 11, 2013 and submitted — Latest diff uploaded

Information

Review Board
1.7.6

Reviewers

timezone is declared 20char long in models.py or django-evolution script whereas some timezones are greater
America/Argentina/Buenos_Aires is the longest => 30 chars

this issue can also be seen in current master branch
$ ./reviewboard/manage.py evolve --hint --execute
$ mysql -u reviewboard -p -D reviewboard -e "desc accounts_profile;" |grep timezone
timezone	varchar(30)	YES		NULL