Add route for locations (CEBES014T1) in enrollments and school classes

- Mount route under '/api/v1/enrollment/location'
- It should list the location names for enrollments and school classes
- The reponse format is a lista of objects with each object having a location_id (CEBES014T1) and a description

Signed-off-by: João Victor Risso <joaovictor.risso@gmail.com>