Finish writing error messages to log rather than using print()

[philip-schrodt]

There are still an assortment of these -- very low probability contingencies, probably -- but they should go to the log, since generally no one is watching the screen except when debugging.

[ahalterman]

There's also a lot of info getting printed out during coding that would be nice to have logged rather than printed, while you're at it. For example, I get output like this for every story:

Processing story 5770266d172ab87ec6dc98ef

 5770266d172ab87ec6dc98ef_0
 FINANCE MINISTER MOSHE KAHLON ON SUNDAY SAID THAT THE FINANCE MINISTRY HAD SET UP A 24-HOUR `` SITUATION ROOM '' TO KEEP TABS ON ECONOMIC REPERCUSSIONS FROM THE UNITED KINGDOM 'S THURSDAY VOTE TO BREAK FROM THE EUROPEAN UNION .
NPgm-rec-2: ~GOV
NPgm-rec-1: ISRGOVMED
NPgm-rec-1.1: (u'ISRGOVMED', [u'>090401'])
NPgm-rec-2: ~GOV