DateTime obeys simple algebra laws), and added a test for subtraction
over daylight savings boundaries.

especially in the light that the given examples are push and pop!

implied classes with empty doc strings "inherited" bogus doc string
from Interface class, and interface class attribute not being set
correctly during init.

parsing message headers

Thanks Evan.

the roles if it is called with a wrapped object.

Changed the role computing logic to always use aq_inner when getting
a parent to make sure it follows the containment context.

rfc1123_date(): Put back in the check for defaulted timestamp, so we
don't get exceptions in that case.  Fixes failure on writing ftp
documents, at least.

Looks like the 'format' parameter is unused and inappropriate, but i'm
leaving that for someone in the know to repair.  (They should pull out
my 'XXX' comment/note, at that time.)

they get reindexed.