Use of the weight value in the modula distribution.

The following config can now be set:

   distribution: modula
   servers:
    - 192.168.0.1:6379:2
    - 192.168.0.2:6379:2

That behaves exactly like this:

   distribution: modula
   servers:
    - 192.168.0.1:6379:1
    - 192.168.0.1:6379:1
    - 192.168.0.2:6379:1
    - 192.168.0.2:6379:1

This code doesnt change the current behavior of modula distribution with servers using weight of value 1.