Modified add osd script to set weight properly instead of blindly
setting it to 1.0. Now it is calculated based on size of disk
relative to 1TB.
1TB disk   => weight 1.0
832GB disk => weight 0.81

Change-Id: I4c8b84d796bf6ca1e9d9b81524c64b3b51d4a0f9
Closes-Bug: #1372659