Python3: fix syntax issue in _encode_item()

In Python 3, this is not a valid syntax:

    def _encode_item((k, v)): ...

Pass a single parameter to the function, and start by unpacking.

Change-Id: I73743073113a4696b9adc79bdb646575794c1e2b
added new column binary to the listing of agents

Change-Id: I057185ef2b6e248271597e81a6bef44c2ad8d148
Closes-Bug: #1313702
Merge "added new column binary to the listing of agents"
Merge "Python3: fix syntax issue in _encode_item()"