Update license date on all files. No functional changes.
Include __BEGIN_DECLS and __END_DECLS (i.e., extern "C" blocks) to play
well with C++.
Update licenses to 2017.
Update license. No code changes.
Include copyright in all files. There are scripts to do bulk
replacement of the copyright if desired.
Prep for storing signatures in the log. This puts the log into network
byte order for portability and adds a few fields. The datum still needs
to be extended, the signature actually stored, etc.
Add new routines ep_net_hton64 and ep_net_ntoh64 to do network to
host byte order swapping on 64-bit values.