Fix internal link in readme

Now submitted to the proper branch :)
Merge pull request #48 from miclf/patch-2

Fix internal link in readme
Get user id by model primary key name

Get the user id by the primary key name defined in the User model, instead of assuming "id" as primary key.
Get user id by model primary key name

Get the user id by the primary key name defined in the User model, instead of assuming "id" as primary key.
Merge pull request #51 from trizz/develop

Get user id by primary key name
Merge pull request #52 from VentureCraft/develop

User ID update and documentation link fix