Small bug in samples class when retrieving items

[alina-muellenmeister]

Description

Retrieving items from a samples object causes a Value Error ValueError: Index t invalid in samples.py in line 390.
Example: Retrieving an item in test_samples() in test_samples.py:

  outputs = get_outputs(0.2)
  resultsdir = tempdir/'samples_results'
  resultsdir.mkdir(exist_ok=True)
  s = ss.Samples.new(resultsdir, outputs, identifiers=["p_death"])
  s[0]

This was likely missed in the starsim 2.0 update and is fixed by updating from t to timevec.

[alina-muellenmeister]

Added an option to disable printing Zip files saved to..., as it disrupts the tqdm progress bars when running simulations with Celery workers on VMs (purely for aesthetic purposes ;))

[cliffckerr]

Looks great, thank you!