[webapp] Webapp should decode contents of TRCs and certificates

[mlegner]

The webapp currently shows TRCs and certificates in (unreadable) base64-encoded form. It would be nice if it could decode it to a human-readable form.

[matzf]

The "Trust" tab is now completely broken as the TRCs/certs are no longer in json format and the files have been moved. The webapp fails to load the certs and the page simply does not display anything.
The TRC and certificates are now in a binary format (ASN.1 for TRCs, x.509 (PEM) for the certificates) and can be decoded by invoking scion-pki trcs human <path/to/*.trc> and e.g. openssl x509 -in <path/to/*.pem> -text.

It's not clear to me what the purpose this "Trust" tab serves here. Even in "human readable form", the certificates are not really easy to digest. To me it would seem ok to simply remove this functionality.

[mlegner]

It's not clear to me what the purpose this "Trust" tab serves here. Even in "human readable form", the certificates are not really easy to digest.

I think its purpose was to explicitly show how these certificates look to users exploring SCION to get a feeling how the control-plane PKI works.