push: feed pushoperation object to _pushbookmark function
This will able the bookmark synchronisation to have full information on the
ongoing push and pass information to other operation.
changeset = '{rev}{tags}{bookmarks}{parents} {node|short} {date|isodate} {author|user}\n {desc|firstline|strip}\n\n'
changeset_quiet = '{rev}:{node|short}\n'
changeset_verbose = '{rev}{tags}{parents} {node|short} {date|isodate} {author}\n {desc|strip}\n\n'
start_tags = '['
tag = '{tag},'
last_tag = '{tag}]'
start_parents = ':'
parent = '{rev},'
last_parent = '{rev}'
start_bookmarks = '['
bookmark = '{bookmark},'
last_bookmark = '{bookmark}]'