Fix improper initialization of the variable m_lastFseq in the constructor of castor::tape::tapeserver::daemon::TapeWriteSingleThread (#1247)

As canceling of stage request implemented as DELETE, files that still in
the flush queue doesn't 'exist' in catalog.

the new conf options to cta.conf file is added:

gRPC TlsCert /path/to/cert.pem
gRPC TlsKey /path/to/key.pem
gRPC TlsChain /path/to/chain.pem

the CTA service is independent from gRPC, thus we want to decouple them
from each other.