Middlerawre that "translates" ids in results to strings

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

reqQueryFields would duplicate inner joins if the same property appeared in
dims and filter.

This adds the option to have values accepted only by one parameter, instead of
globals, like it was then

It uses a object to set the url fields accepted and it's values, parse the
fields and build the query with the values automagically

- Add proper error handling in libs/db/query_exec. Uses a catch function after each then to proper capture database errors and report them to the user.
- Add logging the error stack when a database query error occurs.
- Change error message reported in the response when a database query occurs, because the person making the request does not need to know about an internal error in the database.

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

- Add middleware to check for the appropriate Node version. This relies on the
engines.node flag being set on package.json.

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

Sanitize the location in the result

Closes simcaq/SCRUM#42

This reverts commit bfe64623, reversing
changes made to 9c8cfa58.

Also the req.sql attribute is being created ("injected") before all routes

Related: simcaq/SCRUM#18