If token is not already available, call gs_auth to either load
from cache or initiate OAuth2.0 flow. Return the token -- not "bare" but,
rather, prepared for inclusion in downstream requests. Use
access_token() to reveal the actual access token, suitable for use
with curl.
google_token(verbose = FALSE)include_token_if(cond)
omit_token_if(cond)
a request object (an S3 class provided by httr)