only list significant popit instances on popit.mysoc

Display standard list on other sites but hardcode a curated list on
popit.mysociety.org for speed.

Fixes #369
Merge remote-tracking branch 'origin/ui-refresh' into ui-refresh
Fix some of the failing browser tests
Make sure the correct version of sass is installed
Ensure compass is installed and the correct version
Fix list of instances on the homepage
Revert "Fix list of instances on the homepage"

This reverts commit 4631bd44d822b3c39f7f7af1433ceaca86c3be9e.
Make sure zeroclipboard is copied across
multi-colun layout and boxed initials for person/organization listing pages
homepage button "log in to edit details" when instance description set
use correct config variable for instance list page special case

Fixes #369
Fix in place forms not being populates when editing collections

The code to associate the elements on the page was relying on sections
with class names which have since been removed so change to using uls
and add class names to those
Merge branch 'ui-refresh'
Replace edit details with copy api url on homepage

This makes it easier to access and can be changed in the future to
something more sensible if need be.
Fix placement of newly added list items

Update how we work out where to add new items to lists to cope with
the changed page layout
Merge remote-tracking branch 'origin/master'
remove nested model from the collection rather than destroying them

if we destroy them then if the list of models has been fetched from the
server the backbone events do not get called in the correct order and we
end up trying to sync the nested model which does not work as it doesn't
have a url. By removing it from the collection we make sure to trigger
the correct series of events to cause the sync to happen on the parent
model.

This was only a problem on deleting more than one item from a list as
the initial list is loaded from JSON on the page and treated differently
by backbone as it thinks it's new.

Fixes #283
populate contents of membership pop-up dialog

set ul class so the correct event is assigned
also fetch the post details when instantiating the dialog so that is
correctly populated
do not refresh page when editing memberships

previously when you edited a membership this caused the whole page to
reload which could result in losing data if you were editing names etc
so instead we do all the updating by ajax and add the new elements in
place.
fix adding new membership dialog launching

Incorrect variable name was causing it to fail