(the latter also in frozenmain.c)
* ceval.c: global 'killprint' flag raises exception when printing an
expression statement's value (useful for finding stray output)
* timemodule.c: add asctime() and ctime(). Change julian date to
1-based origin (as intended and documented).
* Removed unused DO_TIMES stuff from timemodule.c. Added 'epoch' and
'day0' globals (year where time.time() == 0 and day of the week the
epoch started).
