Handle errors in AlterParitionReassignment client responses

[pecigonzalo]

This is basically a copy of the problem found in #103.

I suspect there could be other instances of the same pattern in other places.

Example error:

Response contains errors: map[0:[39] Invalid Replica Assignment: the replica assignment is invalid: Replica assignment has brokers that are not alive. Replica list:ArrayBuffer(0), live broker list: Set(1, 2, 3) 1:[39] Invalid Replica Assignment: the replica assignment is invalid: Replica assignment has brokers that are not alive. Replica list: ArrayBuffer(1, 2, 0), live broker list: Set(1, 2, 3) 2:[39] Invalid Replica Assignment: the replica assignment is invalid: Replica assignment has brokers that are not alive. Replica list: ArrayBuffer(2, 0, 1), live broker list: Set(1, 2, 3)]

TODO:

• Add tests

[hhahn-tw]

Thank you once more for your contribution!