Purple Air Api Versions Save

Thanks to @pjrobertson for the following contributions:

• Implement #95
• Fix #88
• Add new historical methods:
  • get_all_historical
  • get_historical_between
  • get_all_historical_between

Additional changes:

• Make some methods private
• Add more types
• Update documentation

• Fix #86
• Fix #89
• Remove no_child filter as all Sensors have children
• Update dependencies

• Update code using requests_cache dependency for #81
• Use sessions instead of monkey-patching requests
• Pin dependency versions

• Add DOI for #72
• Update documentation method signature for #77
• Update column names for #78
• Update documentation for #78

• Fix #70 during initial setup
• Support custom start date to resolve #71
• Support new ThingSpeak API URL structure to resolve #73

• Add temporary query string to initial call to make the app work while we wait for the new PurpleAir API launch

• Add temporary query string to initial call to make the app work while we wait for the new PurpleAir API launch

• Organize FAQ and Docs files for #56
• Improve test coverage
• Add filter for outlier temperatures to sample script
• Fix timestamp conversion for #60

• Better filter logic when sending network sensor data to DataFrames for #49
• Add filters for sensors with and without children for #49
• Better error formatting when given bad or missing data
• Update sample code and documentation for to_dataframe, add notes about Channels
• Fix bug where the library attempted to get Statistics data from the wrong field
• Rename 'a' and 'b' to 'parent' and 'child' throughout app
• Add missing ADC, RSSI, and 1day_avg fields to data exports for #51
• Add as_dict and as_flat_dict as Channel methods for #52
• Add as_list to Sensor methods
• Simplify logic for as_dict and as_flat_dict for Sensor

• Add several data points previously not parsed
• Raise better errors on failures to instantiate sensors
• Simplified sensor and channel parsing logic
• Add some missing type hints
• Add better tests for exporting data