Checks for existence of ocsp and crl pointers.
TLD list.
Added checks for not well defined expiration date.
Added more methods to cert
Added get_extensions method.
Let tests depend explicitly on their testing library.
Adding a test to the TESTS variable will both build and run it.

Have it so adding a simple test is, uh, simple.
Changed cert_db to use Certificates and log_ids.
Moved database related files to ct/client/db.