Update pykeg drinks

update-drinks.py

# Manually reset the volume of all drinks in a session.
# You should run this by hand in "kegbot-admin.py shell"
# Be sure to run "kegbot-admin.py kb_regen_stats" after doing so.

ML_PER_TICK = 1.0/2200   # change me
SESSION_ID = 123         # change me

# Should not need to edit past here.

from pykeg.core import models
session = models.DrinkingSession.objects.get(seqn=SESSION)
drinks = session.drinks.all()

print "Adjusting session: %s" % session
for d in drinks:
  d.volume_ml = d.ticks * ML_PER_TICK
  d.save()
  print "  + %s" % d