Updates to documentation.
Improvements to API key handling so that API keys are checked for on package load.
Increased test coverage
Creation of generic download function to ease code maintenance
Tweaks to error messages
Added error messages to
fixer_convert() for amounts
>=100,000 and <=0.
Added conversion from UNIX time to yyyy-mm-dd HH:mm:ss for
Increased test scenarios.
Removed need to declare account type
Fixed error that broke entire
Included proper citation information
Fixed some spelling mistakes and improved clarity of vignette text