Change text and remove some unnecessary space

Last updated was a confusing label as it was really the most recent data
points _timestamp (sorted by _timestamp)
Fix spelling of 'quarter' in comment
Add summary email entry point

This commit adds an npm script for `summaries` which currently does
nothing other than parse the summary JSON configuration file and
log out that it would send email to users.
Merge pull request #34 from alphagov/feature/update-notifier-templates

Change text and remove some unnecessary space
Change start entry point to out-of-date

Now that there are 2 entry points, it makes sense to change this
to not be `npm start` any more.
Merge pull request #35 from alphagov/add-entry-point-for-summary-email

Add entry point for summary email