Bump logstasher to 0.4.8

To get https://github.com/shadabahmed/logstasher/pull/20
Merge pull request #52 from alphagov/bump_logstasher

Bump logstasher to 0.4.8
Upgrade to Rails 3.2.17
Merge pull request #53 from alphagov/rails-3-2-17

Upgrade to Rails 3.2.17
Remove invalid need ID being sent to panopticon.

This is currently blocking deployment because panopticon rejects
non-maslow need IDs.  Fix this by removing it here.  The correct need ID
for this application can be added in the Panopticon UI.
Merge pull request #54 from alphagov/remove_need_id

Remove invalid need ID being sent to panopticon.