Separate out the people related to child places

It was confusing to present both people associated with the place
itself and those associated with child places in the same list
especially since the criteria for their conclusion was different.
Make Place.related_people include positions, and take a position filter

The people who are returned by Place.related_people were determined by
their positions, but those positions weren't easily accessible in the
template that displays them; this was confusing because you wouldn't
see *why* those people were being displayed.

In addition, each country has different criteria for considering
positions important (e.g. in some countries it might only be MPs,
in some it might be senators, and anyone who's a member of a particular
house).  To deal with this, related_people now takes a position filter
which defaults to a country-specific function.
Also use related_people for child places

It was a strange inconsistency that different criteria were used
in a uniform list of people when finding those associated
with the place itself, and those associated with a child place.
This commit switches to using related_people for both.
Factor out common template code in the place's people page
If there are no positions for child places, don't output the heading

This adds a helper method called related_people_child_places, which
returns the results of related_people for each child place, and
uses that to return the list of people associated with child places.
Make the Place overview page only show relevant representatives

There was a strange inconsistency where the People sub-page for
a Place showed:

  - people who had a current significant position associated with
    the place

  - and people who had a current significant position associated
    with any child place of the place

... whereas the overview page would show people who had any
political position associated with the place (i.e. it would
include extra people who had positions in a particular council
for a place, or local party heads for the place, etc.)  As well
as the inconsistency, it wouldn't be immediately clear why those
people were appearing on the overview page, and they weren't
really "representing" the page as the section heading suggested.

This commit changes the overview page to also use the
related_people method to find those to show on the front page.
Merge branch 'issues/1254-related-people'
Fix an unclosed <a> tag and use a preposition consistent with elsewhere
Add a short README for the country package
Switch to using nose as a test runner
Add yanc ("Yet another nose colorer") for coloured test output
Move the settings module into a settings package

This is to support multiple settings modules in the future, as
suggested in Two Scoops of Django.
Add a settings module only run running the tests

This can be used with, for example:

  ./manage.py test --settings=pombola.settings.tests
Fix a failing test

Nose looks for methods that contain test after any word break:

  https://nose.readthedocs.org/en/latest/writing_tests.html#writing-tests

In this case, get_test_file_content is a helper method rather than
a test, so mark it with @nottest.
Only try to include country-specific URLs if COUNTRY_APP is truthy

For running the base tests, we'll set COUNTRY_APP to None, but
without the change in this commit, it would error on loading
urls.py.
Using assertIn will give a better error message on test failure
Update a test that uses the Google geocoder for its current results

This is just a temporary fix; really the test shouldn't be relying
on a network connection and hitting an external API, and instead
sample data returned from the API should be saved and supplied in
the test, as suggested here: http://stackoverflow.com/a/7564101/223092
Fix incorrect references to the settings module

The settings module should never have been referred to as
pombola.settings instead of from django.conf; this was exposed
by the move of the settings module into a settings package.
Make sure that the interests_register tables are created

Nose tries to run the interests_register tests, but they will
fail unless the interest_register app is added to INSTALLED_APPS,
because its tables won't be created in the test database.
Move core_set_iebc_api_ids.py, which is Kenya-specific