Encoder Package

This is a simple wrapper to the json.Marshal, which adds ability to skip some fields
of structure. 
In pair with this changes https://github.com/codegangsta/martini-contrib/pull/94 you can easily manipulate visibility  of passwords, statuses, activation codes, etc... 
Here is a complex example https://github.com/3d0c/skeleton, see models/schemes.go, e.g. UserScheme.