Fix PositionTitle's get_absolute_url()

This was broken by the change to the naming of the position
views, and meant, for example, that the autocomplete in the
search view would return 500 errors with the term "memb".
Allow changes to position order on the organisation' people page

This also changes the default ordering to be by the legal_name
of each person, which makes more sense as a default, I think.

This is part of the fix for #659.
Whitespace changes
Consolidate repeated code
Add identifiers to the admin, and as inline to place, person and organisation. Closes #668
Merge branch 'issues/668-identifiers-admin'
Enable tables in markitup
Add table styling to the infopage CSS
Style the homepage markdown correctly
Add example of tables to the sampler
Zimbabwe: replace 'Mzalendo' or 'Mzalendo Zimbabwe' with 'Kuvakazim'
Ignore more config files.

Anyone using bin/switch_country.py to manage several different
Mzalendo setups is going to have an assortment of config files
general-*.yml.

We may as well exclude them all from git.
Change overview to have correct suffix
Zimbabwe: update with logo and colours from Peter Teuben

These changes are just to make the logo and colours match
the Kuvakazim site here: http://carma.astro.umd.edu/ztest/

The logo was provided by Peter Teuben.
Merge branch 'zimbabwe'
Return unicode to the admin to display, should fix 500 on /admin/task/task on MzKe
Update SA people navigation to better links.
Add models for representating relationships between organisations

We need this for representing the link between constituency
offices and parties, but it would also have been useful for
representing party -> coalition relationships around the
Kenyan election.
WiP
fixup! Add models for representating relationships between organisations