App can be run using shiny_app.R
UI and Server definitions are in the shiny_app directory
Occur in classes in the classes dir
Pitcher and hitter classes share a super class (data_fetcher.R) with a set of methods for getting and tranforming data.
Data is from baseballsavant.com and appac.github.io/mlb-data-api-docs/ . Be reasonable when pulling data from these sites