servelog: use simplejson and the % operator for python versions < 2.6
Both the json module and str format operator are new in version 2.6, so replace
them with the simplejson module and the % operator, respectively.
# WARNING: when these hooks run they will entirely destroy and rewrite
# ~/.ssh/authorized_keys
[extensions]
hgext.purge =
[hooks]
changegroup.aaaab_update = hg update -C default > /dev/null
changegroup.aaaac_purge = hg purge --all > /dev/null
changegroup.refreshauth = python:mercurialserver.refreshauth.hook