dbdump: add slave support
dbdump: add slave support

* Adds support for running dbdump on replicated DB slaves.
  dbdump will take care of stopping slave replication before
  dumping and continuing it after dump.

* New CLI parameter, --slave=HOST, will take the hostname of
  the desired slave to dump from or if empty, CFG_DATABASE_SLAVE
  is used

Conflicts:

	modules/miscutil/lib/dbdump.py

tiborsimko/invenio,inveniosoftware/invenio,inveniosoftware/invenio,tiborsimko/invenio