Include instance name in confirmation email

Add the slug name to the text of the email as well as including it in
the confirmation URL.

Fixes #455
make create new organization an actual page

make person-new action into entity-new action and add in switching code
so it works with organizations as well.
update new organization template
apply new person html to organisation page

as part of restyle of page to move lots of the non essential details
into tabs etc
reformat entity-new to make subsequent edits clearer

split out define stuff per line and indent everything accordingly
Add autosuggest for organization name on new org page

to help prevent duplicate organization creation.
Needs styling
make organization classification a select2 dropdown

So you get suggestions of existing classifications but can also create
your own.
Needs styling.
remove unhelpful breadcrumbs from organization page header
ask for organization type if not present

and clicking on it activates editing mode
update html for items in tabs
JSON API -> Get this data as toolbar button text

Just a bit more friendly
display organization placeholder image on new org page

for layout consistency with new person and edit org page
only apply new org classification select2 on new org page

we need to set the classification to display in it on the view org page
but as we don't have that on the new page we need to handle it
differently to stop complaints about missing variables
reformat organization-edit.js to make later changes obvious
replace classification with select2 on org edit page

so we can see the list of existing classifications
we need to specifically hide the input as the code to turn on the
editing interface overrides some of the select2 setup code resulting in
the original input displaying and a confusing double display of the
selected value
Merge remote-tracking branch 'mysoc/488-organization-page-overhaul' into chris-dev