Bug 20941: Add Illrequest->getType method

Bug 20941: Add Illrequest->getType method

This patch adds a method to the Illrequest object enabling it to return
its type, which is stored as an Illrequestattribute object

To observe broken state:

- Do not apply patch
- Ensure you have at least one Interlibrary loan created
- In OPAC view, go to "your interlibrary loan requests"
  - => TEST: Observe that the "Request type" column is not populated
  - Click on "View" for one of the requests
  - => TEST: Observer that the "Request type" row is not populated
- In Staff view, go to "ILL requests"
- Click on "Manage request" on a request
  - => TEST: Observer that the "Request type" row is not populated

To Test:

- Apply patch
- In OPAC view, go to "your interlibrary loan requests"
  - => TEST: Observe that the "Request type" column IS populated
  - Click on "View" for one of the requests
  - => TEST: Observer that the "Request type" row IS populated
- In Staff view, go to "ILL requests"
- Click on "Manage request" on a request
  - => TEST: Observer that the "Request type" row IS populated

Signed-off-by: Niamh.Walker-Headon@it-tallaght.ie
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>