refactor modelDomains() and modelInfo()

[jonathancallahan]

Looks like providing access to this information grew organically and is ready for a refactoring.

The information we need is quite small and is most useful as a dataframe. So the AirFireModeling.R function should just define a complete bluesky_modelInfo dataframe as a package data object, avoiding the unnecessary function definitions and calls.

The following examples show how to create package data in R code. This is appropriate for package data files that are small and hand-crafted, like the model info.

https://github.com/MazamaScience/MazamaLocationUtils/blob/master/R/MazamaLocationUtils.R coreMetadataNames

https://github.com/MazamaScience/MazamaSpatialUtils/blob/master/R/MazamaSpatialUtils.R CONUS

https://github.com/MazamaScience/PWFSLSmoke/blob/master/R/PWFSLSmoke.R AQI

• [x] create bluesky_modelInfo dataframe in AirFireModeling.R
• [x] replace any calls to modelDomains() or modelInfo() with this dataframe
• [x] remove modelDomains() and modelInfo() functions

[hmrtn]

bluesky_modelInfo is now an internal dataframe. It no longer contains subdirectory information strings, as this was throwing very strange errors when using bluesky_availiablemodels().