OGDS sync: Remove old unused shell script.
Fix incorrect and unnecessary logger reuse.
Add some debughelpers to og.base (previously in og.maintenance).
Remove redundant WARNING prefix in log messages, PEP8.
Rename `og.ogds.base.ldap_import` to just `sync` and move `ldap_util` into it.
Remove redundant .get() default values, PEP8.
OGDS Updater: Make log messages more explicit.
OGDS sync: Unify OGDS synchronization so there's a single function

that does the sync and that can be called from anywhere.
OGDS sync: Add a `bin/instance sync_ogds` zopectl command that

can be used from a cron job.
Merge pull request #623 from 4teamwork/lg-unify-ogds-sync-implementation

Unify OGDS sync implementation