Add script to import legacy pages and translations

[jgmize]

Add json data from existing (legacy) site
Add django_extensions and six to requirements
Run script with './manage.py runscript create_pages'

[jgmize]

@glogiotatidis would you mind taking a look at the Jenkins console output from the failed build and see if you can figure out the devicemapper error we're getting?

[glogiotatidis]

@jgmize there is a docker / fig race condition going on. afaik this is unsolved. Best work around atm is to retrigger the tests by saying:

[glogiotatidis]

test this please

[jgmize]

@glogiotatidis there's still a little more work to do on this, but with the code in the latest update I've successfully converted the german translation from the legacy json to a po file: https://github.com/mozilla/masterfirefoxos-l10n/blob/master/de/LC_MESSAGES/django.po

[glogiotatidis]

I believe that should be ./manage.py db_strings

[glogiotatidis]

Nevermind, got it

[glogiotatidis]

I think we need a fixture with the generated Pages to load it on dev and prod. Direct commits to locale directory with db-strings will be overwritten by dev's empty database.

[jgmize]

With the latest updates there is a single command to import pages and translations from the legacy data:
./manage.py runscript import_legacy_pages_and_translations

Please test this locally, and I'll work on some acceptance tests text. I believe we should be able to run this command in dev and prod to address the empty db issue.

[jgmize]

test this please.

[jgmize]

As we discussed in the dev meeting, I'll merge this now and add acceptance tests and further refinements in future PRs.