[Nitro] schema_inheritance

[Emmanuel Piperakis]

> use:
>
> is SchemaInheritanceBase
>
> perhaps we can improve the name.

G. the initial email I posted reported a bug in the 0.26, where when I use 
the schema_inheritance only the frist subclasss' fields are added to the 
superclass. That must be realy easy to fix, and it worked for 0.25 and it 
prevents me from upgrading.

e.g

class Project
  property :koko, String
  schema_inheritance
end

class FProject < Project
  property :haha, String
end

class DProject < Project
  property :kaka, String
end

ONLY :haha is added and NOT :kaka. I tried switching the order of the 
classes (first DProject and then FProject) and then only :kaka was added 
to the table and NOT :haha, therefore there a very simple problem. You 
only take one subclass...

Could you please fix this?

Thanx

Emmanouil Piperakis (epiperak at cs.ntua.gr)
{To explore is Human, to Create is Devine,
  To teach is Primal, to Rule is Sin}