Add script to auto delete excess data in the database

[AndyGrant]

After some time, all of the Result objects for a given test may be deleted. Leaving only the final results, cutting out the massive amount of data due to the 40+ machines connected. Additionally, the EventLog may also be cleared.

I have been doing this by hand every few months to keep the database small, but each time I forget how to do it.

[AndyGrant]

from OpenBench.models import .

<model>.objects.all().delete()

from django.db import connection
cursor = connection.cursor()
cursor.execute('vacuum')

[AndyGrant]

from OpenBench.models import *

x = Result.objects.all().delete()
y = Machine.objects.all().delete()
z = LogEvent.objects.all().delete()

[ Nothing else needed for MySQL ]