Make pipeline work for pre-2019 data

[gailin-p]

Where per-fuel type 930 data isn't available (before July 2018), should default to other hourly profile methods. This would allow the pipeline to work for older years

[grgmiller]

Whenever we add new years of data, there are a few things we need to do:

• Check whether the data to be downloaded uses the same url pattern as before
• For any data not loaded from pudl, check that column names and positions are the same
• Check any steps that involve manually updating data (any step that uses a table in data/manual/ to make sure they apply to each year
• Run the full pipeline and examine any validation messages