Add es_score to documents

This is primarily for debugging scores
Reduce time boost and scope to announcements

Also increase minister boost as in some cases other documents score
higher - becuase of the title boost

Specify the search_format_types must be announcement
keep the score attribute name consistant
Update advanced search score test
switch yajl-ruby to and use unicorn in startup

Was seeing segfaults with the JSON gem, with some content with
interesting chars:

prepare, respond and recover. This British Red Cross led project is
about ‘Wor
Readme update