Fixes - hepspec weights schema integer problem

Pig schema was defining hepspec weights as integers but the underlying tuple (in MyUDF.SiteAvailability) stored String objects.

The hepspec weights persisted as string during the final output store in Mongo. 

With fix c624b94233fdb0a2c94b4f06db3e02f8199d1670 weight tuples now contain parsed integers and they persist as integers in mongo as well.