Fix explicit nonce handling

Hi Matthias,

I have done the following:
- added a default logging config file to be used for running tests
- fixed a bug in the Record class' decryptAEAD() method which prevented Scandium to work properly with the CyaSSL library which does not use epoch + sequence no as "explicit" nonce part when encrypting payload data as is assumed by the decryptAEAD() method