Documentación de las rutas soportadas

Se añade documentación sobre las rutas soportadas cuando se ejecuta en
modo ‘develop’ tanto por via web ‘/apiDocs’ como por consola al
arrancar el servidor.
Added name to login error response

Added field name to error response in functions requiresLogin and
hasAuthorization
Check groupbuy name length

Added check groupbuy name must be between 10 an 80 characters
Check username length

Check username length and change error message
Change users and groupbuys routes

Change users and groupbuys routes to use mongoose-rest-endpoints module.
Added tests

Added tests to users and groupbuys
Updates packages.json

Comment dependencies on passport-* (except local).
Update version of body-parser, express-session, forever, glob,
mongoose, morgan.
Added dependencies on mongoose-file, mongoose-rest-endpoints,
multiparty modules.

Updates development dependencies.
Addlocale core.Create
Creation of .error-message style

Create a new style to use with error messages.
Added build and dependencies info in README.md