[auth] pass `repo` instead of `vreg` to SessionManager and AuthenticationManager
Those object actually need a repo object to connect and create new session
object. They used to retrieve the repo object using
``vreg.config.repository()``. I'm trying to sanitise the initialisation stack
and get ride of ``config.repository()``, a function that mix factory and cache.
Retrieving the vreg from the repo is trivial (``repo.vreg``) so we now pass the
repo object instead of the vreg.
from yams import schema2sql as y2sql
dbhelper = repo.system_source.dbhelper
rdefdef = schema['CWSource'].rdef('name')
attrtype = y2sql.type_from_constraints(dbhelper, rdefdef.object, rdefdef.constraints).split()[0]
cursor = session.cnxset['system']
sql('UPDATE entities SET asource = source WHERE asource is NULL')
dbhelper.change_col_type(cursor, 'entities', 'asource', attrtype, False)
dbhelper.change_col_type(cursor, 'entities', 'source', attrtype, False)
dbhelper.change_col_type(cursor, 'deleted_entities', 'source', attrtype, False)