I'm using RB 1.7.6 on CentOS 6, Python 2.6.8

What's the URL of the page containing the problem?
Any page
What steps will reproduce the problem?

easy_install -U reviewboard
rb-site upgrade /var/www/html/reviewboard


What is the expected output? What do you see instead?
I'm expect no errors, but get:
Rebuilding directory structure

Updating database. This may take a while.
The log output below, including warnings and errors,

can be ignored unless upgrade fails.
------------------ <begin log output> ------------------

Creating tables ...

Creating table accounts_trophy

Creating table attachments_fileattachmenthistory

Creating table diffviewer_rawfilediffdata

Creating table notifications_webhooktarget_repositories

Creating table notifications_webhooktarget

Creating table webapi_webapitoken

Upgrading Review Board from 1.7.6 to 2.5.1.1

There are unapplied evolutions for auth.

There are unapplied evolutions for contenttypes.

There are unapplied evolutions for accounts.

There are unapplied evolutions for attachments.

There are unapplied evolutions for changedescs.

There are unapplied evolutions for diffviewer.

There are unapplied evolutions for hostingsvcs.

There are unapplied evolutions for notifications.

There are unapplied evolutions for reviews.

There are unapplied evolutions for scmtools.

There are unapplied evolutions for site.

There are unapplied evolutions for webapi.

Adding baseline version for new models

Evolutions in webapi baseline: webapitoken_jsonfield_null

Evolutions in notifications baseline: webhooktarget_extra_state, webhooktarget_extra_data_null

Project signature has changed - an evolution is required

Installing custom SQL ...

Installing indexes ...

Installed 0 object(s) from 0 fixture(s)

ERROR:root:Unexpected error: u'index_together'

Traceback (most recent call last):

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/management/commands/evolve.py", line 65, in handle

    self.evolve(app_labels, options)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/management/commands/evolve.py", line 125, in evolve

    sql.extend(self.evolve_app(app))

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/management/commands/evolve.py", line 164, in evolve_app

    app_mutator.run_mutations(mutations)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 279, in run_mutations

    self.run_mutation(mutation)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 268, in run_mutation

    model_mutator.run_mutation(mutation)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 165, in run_mutation

    mutation.mutate(self, self.create_model())

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutations.py", line 785, in mutate

    mutator.change_meta(self, self.prop_name, self.new_value)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 136, in change_meta

    'old_value': self.model_sig['meta'][prop_name],

KeyError: u'index_together'

Traceback (most recent call last):

  File "/usr/bin/rb-site", line 9, in <module>

    load_entry_point('ReviewBoard==2.5.1.1', 'console_scripts', 'rb-site')()

  File "/usr/lib/python2.6/site-packages/ReviewBoard-2.5.1.1-py2.6.egg/reviewboard/cmdline/rbsite.py", line 1922, in main

    command.run()

  File "/usr/lib/python2.6/site-packages/ReviewBoard-2.5.1.1-py2.6.egg/reviewboard/cmdline/rbsite.py", line 1725, in run

    site.migrate_database()

  File "/usr/lib/python2.6/site-packages/ReviewBoard-2.5.1.1-py2.6.egg/reviewboard/cmdline/rbsite.py", line 452, in migrate_database

    self.run_manage_command("evolve", ["--noinput", "--execute"])

  File "/usr/lib/python2.6/site-packages/ReviewBoard-2.5.1.1-py2.6.egg/reviewboard/cmdline/rbsite.py", line 676, in run_manage_command

    execute_from_command_line([file, cmd] + params)

  File "/usr/lib/python2.6/site-packages/Django-1.6.11-py2.6.egg/django/core/management/init.py", line 399, in execute_from_command_line

    utility.execute()

  File "/usr/lib/python2.6/site-packages/Django-1.6.11-py2.6.egg/django/core/management/init.py", line 392, in execute

    self.fetch_command(subcommand).run_from_argv(self.argv)

  File "/usr/lib/python2.6/site-packages/Django-1.6.11-py2.6.egg/django/core/management/base.py", line 242, in run_from_argv

    self.execute(*args, options.dict)

  File "/usr/lib/python2.6/site-packages/Django-1.6.11-py2.6.egg/django/core/management/base.py", line 285, in execute

    output = self.handle(args, options)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/management/commands/evolve.py", line 65, in handle

    self.evolve(*app_labels, options)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/management/commands/evolve.py", line 125, in evolve

    sql.extend(self.evolve_app(app))

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/management/commands/evolve.py", line 164, in evolve_app

    app_mutator.run_mutations(mutations)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 279, in run_mutations

    self.run_mutation(mutation)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 268, in run_mutation

    model_mutator.run_mutation(mutation)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 165, in run_mutation

    mutation.mutate(self, self.create_model())

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutations.py", line 785, in mutate

    mutator.change_meta(self, self.prop_name, self.new_value)

  File "/usr/lib/python2.6/site-packages/django_evolution-0.7.5-py2.6.egg/django_evolution/mutators.py", line 136, in change_meta

    'old_value': self.model_sig['meta'][prop_name],

KeyError: u'index_together'
What operating system are you using? What browser?
CentOS 5. Firefox 40. 

Please provide any additional information below.
I'm getting same error if install RB 2.5.5.1 on CentOS 6, restore mysql dump from my older RB, and run rb-site install /var/www/html/reviewboard