Print time_t as long long and suseconds_t as long

Print time_t as long long and suseconds_t as long

As per previous commit, this is a simple solution to cope with the
various sizes of time_t on different archs, including those that use 64
bits time_t on ILP32 archs to cope with y2038.

Also:
- convert the time_type/time_format abstraction that used unsigned long
  to inlined long long code
- print suseconds_t as a long, which appears to be the underlying type
  on most Unix systems around

Signed-off-by: Jeremie Courreges-Anglas <jca@wxcvbn.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <87k1zi18lt.fsf@ritchie.wxcvbn.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg15667.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>