Configure base Mapit URL in an initializer.

To be overridden on deploy.  Also pointed at our Mapit instances.
Update authority details when importing.
Skip local interaction rows with invalid SNAC
Make local authority importer continue if a row errors.
Fix SNAC validation to allow county-level SNACs
Add exception_notifications on data import errors.

Required bumping exception_notifier to get
background_exception_notification support.
Strip leading/trailing whitespace from search
Strip excess interstitial whitespace from search
Change Title filter to filter on many fields
Edition.internal_search looks at part titles
Whitespace
Edition.internal_search looks at bodies

This is something we may want to revert, depending on feedback from publisher
users.
Remove a little duplication in progress button generation
Only initialise statsd in one place, and move description method

Sorry for the combined commit. The description method is only used in this
controller so let's declare it here.
Extract progressing editions into a new class

Most of the methods in the Admin::EditionsController were to do with
progressing editions and could more neatly be combined in a command
class. They probably need further refactoring and this gives us a
clearer base from which to do that.

Conflicts:
	app/controllers/admin/editions_controller.rb
Move tests for progress validation into unit tests

Now that I've extracted EditionProgressor our controller can rely
on that to do the right thing. In order to make sure it does do
the right thing it needs some tests. These tests are basically the
tests we already had for the old controller methods moved across.
Document a couple more arguments to EditionProgressor
Replace User object with dummy WorkflowActor

We don't need a full user object to test EditionProgressor, so let's not
have the overhead of creating one.
Remove residue of bad merge
Remove reference to class that doesn't exist in this branch

Sorry