Remove ssldecoder

[Daniel Ruf]

The original owner of ssldecoder shut down the service and cancelled the domain which is now owned by some other person and the website now shows content about bitcoin related stuff.

see https://github.com/RaymiiOrg/ssl-decoder and https://raymii.org/s/blog/Cancellation_notice_for_cipherlist_ssldecoder_and_certificatemonitor.html