Get a FinBIF personal access tokenSource:
Have a personal access token for use with the FinBIF API sent to a specified email address.
Character. The email address to which to send the API access token.
Logical. Suppress messages.
If an access token has already been set then
NULL (invisibly) if
not then, invisibly, a
finbif_api object containing the response from
the FinBIF server.