Add an option for AIP to run all models between two dates

[verovaleros]

We may have data from the past and we want to use AIP to run the models.

I envision something like bin/aip --run-all-models --from YYYY-MM-DD --to YYYY-MM-DD.

[verovaleros]

Now the _rebuild() function takes a start and end date, #70, which will help on this issue.

[verovaleros]

• Add options to run-models to accommodate for at least the four situations described
  • Run all models for a given date
  • Run one model for the default date(today)
  • Run all models in a range of dates
  • Run one model in a range of dates
• Make sure help is clear
• Add tests for at least the run-models command to make sure things work as expected.

[verovaleros]

#74 is done, we should be able to start working on this now.