Fixes and docstrings

Using numpydoc format
  updated module docstring
  added class docstring
  ensured all functions have docstring
  ensured all docstrings are numpydoc
Pylint fixes
  in anticipation of incorporating Pylint into use
  currentData -> current_data
  json > redis because json is a python package
  catch exact exceptions in `connect`
    updated the error handling
    provided exception information in output
Black fixes
  in anticipation of incorporating Black into use
  removed unnecessary whitespaces
  favor double quote, ", over single quote, ', for string delineation
  line size fixes based on default settings
Unit Tests
  Exception change required 1 test to change to 3
    tested both types of expected exceptions (2)
    tested neither expected exceptions (1)
    minor clarity updates
      currentData -> current_data