Have a personal access token for use with the FinBIF API sent to a specified email address.
Value
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.
Examples
if (FALSE) { # \dontrun{
# Request a token for example@email.com
finbif_request_token("example@email.com")
Sys.unsetenv("FINBIF_ACCESS_TOKEN")
finbif_renew_token("example@email.com")
} # }
