Update conflict error to be on path field.

This makes it easier to consume and pass on the error in downstream
applications.
Merge pull request #8 from alphagov/tweak_errors

Update conflict error to be on path field.
Bump rails to 4.1.5

To pick up security updates etc.
Merge pull request #9 from alphagov/bump_rails

Bump rails to 4.1.5
Add rake task to seed reservations from panopticon

This will allow us to switch th using url-arbiter as the source of truth
for which app owns a given path.
Request the minimal artefact view from Panopticon.

Once <https://github.com/alphagov/panopticon/pull/196> is merged and
deployed, this will speed up the seeding significantly; until that time,
it won't have any effect.