Bug 17607: Fix patron definition in Swagger

Bug 17607: Fix patron definition in Swagger

This patch makes the patron swagger definition match the DB schema.
To test:
- Run:
  $ prove t/db_dependent/api/v1/swagger/definitions.t
=> FAIL: 'lastseen' field is not declared in the swagger definition
- Apply the patch
- Run:
  $ prove t/db_dependent/api/v1/swagger/definitions.t
=> SUCCESS: Tests pass!
- Sigh off :-D

Sponsored-by: ByWater Solutions
Signed-off-by: Hector Castro <hector.hecaxmmx@gmail.com>
All tests pass successfuly

Signed-off-by: Lari Taskula <lari.taskula@jns.fi>
Fixed a typo: seed -> seen

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>