minor syntax cleanup (lintjs in pycharm)
update README
update currency detection support and enforce uniform currency
uniform currency in a file is a limitation of this app for now.  sorry to anyone that needs it, though it probably can be fixed fairly easily.
the stripe export file format has changed significantly from when this app was originally written, and a few things have changed that break this app
up next: fix the Fees, Amounts, refunds detection which are currently broken.