Conversion added to gender, period and ethnic group

Now you can join tables with composite foreign/primary keys using RQF. In the
join attribute just use an array of columns that need to be used in the join

* Create routes /enrollment/gender and /enrollment/ethnic_group
* Add gender and ethnic_group to enrollment params in RQF

SQL now is using new schema

SQL is now compatible with DB schema in simcaqdb3

- 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>

Signed-off-by: João Victor Tozatti Risso <jvtr12@inf.ufpr.br>

Change SQL queries in the following routes:

* city
* state
* region
* school
* enrollment

Also, change tests to reflect the new schema where appropriate. Specially in the case of cities, the primary key now becomes pk_cod_ibge (city IBGE code) and, therefore, any query that relies on the city id should use this value instead of the old primary key.

Aliases of fields that have different names were added to ensure compatibility with the UI of LDE.

Please refer to the database repository in order to understand how the current schema works. The corresponding ER diagram can be located there.

Sanitize the location in the result

Related: simcaq/SCRUM#18

Changing apps to follow suggested practices from documentation
and centralizing prefix /api/v1 in the app module.