Bug fixes for the preprocessing steps

[smmaurer]

This PR fixes two bugs that were preventing the preprocessing steps from running (i.e. python baus.py --mode preprocessing).

1. There were a couple of places where the settings injectable needed to be updated to mappings, to reflect a change in yaml files from a few months ago.

2. Due to changes in the base data, I had to loosen a requirement in the allocate_jobs() helper function that's used in the preproc_jobs step.

   The baseyear_taz_controls.csv file lists job counts for each TAZ, which are allocated to specific buildings using this code. If there are jobs but no buildings for a particular TAZ, allocate_jobs() raises an error and crashes.

   This is now happening for a couple of TAZ's. I modified the code to log the problem and move on, which lets the remainder of the preprocessing complete. The mismatches will need to be resolved on the data side (see separate discussion in Slack).

Testing

With these changes, preprocessing runs successfully on my machine (Mac, Python 3.6) using a clean copy of the repo and base data. Output in the log looks reasonable, aside from the problem allocating jobs that's noted above.