Format dollar amounts on transaction cards.

[conroy-ricketts]

Right now, the transaction cards do not have any commas (i.e. $100000 instead of $100,000). We should format the dollar amounts on each transaction card to include commas before every 3 digits. Also, to prevent text wrapping issues, maybe we could instead format a symbol at the end of the dollar amount for large transactions (i.e. $100k instead of $100,000 or $2.3m instead of $2,300,000). It will be up to whoever takes this task to decide whether we should use either symbols or commas.