bookmarks: update known bookmarks on the target on push

bookmarks: pull known bookmarks from server that are newer

bookmarks: add pushkey server-side support

pushkey: add debugpushkey command for testing

pushkey: add http support pushkey requires the same permissions as push listitems requires the same permissions as pull

pushkey: add ssh support

pushkey: add localrepo support

pushkey: add pushkey core

sshrepo: sort arguments All current commands have zero or one args. Future multi-arg commands will want args to appear in a deterministic order.

mq: make 'qdelete <patchidx>' work again. This just backs out 1abd9442727c (a minor code cleanup that accidentally broke qdelete) and adds a test.

bdiff.c: Added support for py3k. This patch adds support for py3k in bdiff.c. This is accomplished by including a header file responsible for abstracting the API differences between python 2 and python 3.

diffhelpers.c: Added support for py3k. This patch adds support for py3k in diffhelpers.c. This is accomplished by including a header file responsible for abstracting the API differences between python 2 and python 3.