Don't puts inside the logger formatter [#63771746]

The puts inside the logger formatter made it so that the logger output was spit out to STDOUT, even if you set the logging device to something else (like STDERR).
Bump the version to 2.0.1 [#63771746]
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Add decode_at_reference_time method to TokenCoder

* Allows a token expiration timestamp to be compared to a given
  timestamp, instead of the timestamp for the current time.

[#68014448]

Signed-off-by: Eric Malm <emalm@pivotallabs.com>
Bump version to 2.1.0

* Minor version bump for addition of
  TokenCoder#decode_at_reference_time.

[#68014448]

Signed-off-by: Eric Malm <emalm@pivotallabs.com>