docs: install: Added Ubuntu and Fedora dependency installation lines
docs: todo: shorten todo entry, thanks to Jon

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
protos: lldp: Add LLDP dissector to netsniff-ng

The order and presence of the mandatory TLVs is not yet completely
checked. Also the Management Address is not yet implemented.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>