Fix #326. Fix #327

327: The problem with wrong data in the committee view is that if a committee files a contribution with a pending (0) committee_id we will then link that committee with all following contributions to other committees with pending ids.  
We cannot be sure that trans_id is unique even within recipients.  Look for complete matches instead.  The transaction id will disambiguate if the same contributor gives two contributions on the same day.

326: I think what was intended was slice(0, half-1) and slice(half-1) not slice(half, -1) but changing them to half balances things better.  e.g. for 6 elements half == 3 so the first column would have 2 elements and the second would have 4 if we use half-1.