Voting poll app and model

[sirex]

Create new voting poll app called polls with one model Poll. Poll model can have following fields:

• created,
• title (required),
• slug (auto slug field),
• registration_close_time (date time, required),
• voting_open_time (date time),
• voting_close_time (date time),
• signing_close_time (date time)
• primary_key (text)
• public_key (text)
• public_key_fingerprint (charfield)

Also register this model to Django admin.