Impacted versions:
9.0, 10.0, 11.0 (Maybe 8.0)
I don't know if it is really an expected behaviour for odoo but I like to expose it

Steps to reproduce:

1. Open an ir.cron record and change it to:
 - interval: minutes
 - next execution date: now + 1 minute

2. Open the odoo server log

Note: I'm using workers=3 but I don't know if there is possible to reproduce it without workers.

Current behavior:

You will see for each cron execution the following output
```txt
...
2018-06-01 16:18:33,432 20686 INFO 333561-11-0-42aff9-all odoo.modules.registry: Invalidating all model caches after database signaling.
...
2018-06-01 16:17:21,527 20687 INFO 333561-11-0-42aff9-all odoo.modules.loading: loading 1 modules...
2018-06-01 16:17:21,535 20687 INFO 333561-11-0-42aff9-all odoo.modules.loading: 1 modules loaded in 0.01s, 0 queries
2018-06-01 16:17:21,594 20687 INFO 333561-11-0-42aff9-all odoo.modules.loading: loading 206 modules...
2018-06-01 16:17:21,718 20687 INFO 333561-11-0-42aff9-all odoo.modules.loading: 206 modules loaded in 0.12s, 0 queries
2018-06-01 16:17:21,989 20687 INFO 333561-11-0-42aff9-all odoo.modules.loading: Modules loaded.
```

Expected behavior:
 - Review if the method that run from the cron really requires a invalidate cache and delete all registries.
 - Disable "minutes" for cron interval because all cache are deleted then is not valid use them.

Video/Screenshot link (optional):

 - [![IMAGE ALT TEXT HERE](https://img.youtube.com/vi/Be4FIeQjgjk/0.jpg)](https://youtu.be/Be4FIeQjgjk)
cr.execute("""
                    SELECT base_registry_signaling.last_value,
                           base_cache_signaling.last_value
                    FROM base_registry_signaling, base_cache_signaling""")
                r, c = cr.fetchone()
                _logger.debug("Multiprocess signaling check: [Registry - old# %s new# %s] "\
                    "[Cache - old# %s new# %s]",
                    registry.base_registry_signaling_sequence, r,
                    registry.base_cache_signaling_sequence, c)
                
                
                if registry.base_registry_signaling_sequence is not None and registry.base_registry_signaling_sequence != r:
                    changed = True
                    _logger.info("Reloading the model registry after database signaling.")
                    registry = cls.new(db_name)
                
                
                
                elif registry.base_cache_signaling_sequence is not None and registry.base_cache_signaling_sequence != c:
                    changed = True
                    _logger.info("Invalidating all model caches after database signaling.")
                    registry.clear_caches()
                    registry.reset_any_cache_cleared()
                registry.base_registry_signaling_sequence = r
                registry.base_cache_signaling_sequence = c
            finally:
                cr.close()
        return changed
    @classmethod
    def signal_caches_change(cls, db_name):