Comment lampoly SNF 2010-04-21 16:33:12: Update Cl2 flow problem

[eenriquez at snf.stanford.edu]

Cl2 flow drops after about 12 minutes.  Line pressure is OK.  Looks like a restricted MFC or filter.  Need to change both.  Pumped out the line to the Cl2 VMB box.  Now cycle purging the gas lines again.