Truncate summaries for DSU
Add summaries to International development funds
Add summaries to medical safety alerts
Truncate after first sentence

After some discussion, truncating after the first sentence seems like
the best option.

This commit does this by gsub everything after a fullstop followed by a
space and an uppercase letter. This functionality can't be achieved with
the normal truncate helper because it works by finding the separator
before the limit, but we wanted it to find the first separator after the
limit.

This way we have a more natural text break, which should hopefully get
around the need for a hard limit.
Merge pull request #133 from alphagov/feature/summaries-and-truncation

Truncation for summaries
Switch to new choices content format

As changed in 77e65b0 on finder-api
Finder fronted find or create subscriber list

Instead of relying on finder-api to ensure that all possible subscriber
lists are create for it, finder fronted is now responsible for creating
the list if necessary.

The main addition to make this work is the ability to create a title
for the subscription from the chosen options, and the signup content
item. How the titles should be created is documented at
https://etherpad.mozilla.org/uK2bBcLupr
Merge pull request #134 from alphagov/better-subscription-options

Better subscription options
Use filter key when creating subscriptions

Tom was right, I was wrong. I forgot that Specialist Publisher would be
posting emails with the field name as the tag key, rather than just
‘filter’. This fixes that.
Raise error if no choice selected, but choices available

This should not be possible, due to validation on front end
Fix subscriptions if no options are available
Merge pull request #135 from alphagov/readd-filter-key

Few fixes to email susbcriptions
Ensure we don't send nil filter attributes

If there are no available filter attributes, we may accidentally send
nil as the filter. This fixes that.
Merge pull request #136 from alphagov/ensure-no-nil-filter

Ensure we don't send nil filter attributes