[IMP] Do not start cron master thread if max_cron_threads == 0
[IMP] Do not start cron master thread if max_cron_threads == 0

gisce/openobject-server,ovnicraft/openerp-server,gisce/openobject-server,MarkusTeufelberger/openobject-server,splbio/openobject-server,gisce/openobject-server,MarkusTeufelberger/openobject-server,splbio/openobject-server,ovnicraft/openerp-server,MarkusTeufelberger/openobject-server,splbio/openobject-server