EVASS: Added evass_realm function

I created the function evass_realm_entity(). I need it to assign the correct realm to database table.

All work fine for less than the table "org_organisation". (All other tables refer to org_organisation, so it is really important :) )

Let me explain:
Before I created the  evass_realm_entity() function when I had created a new organisation, its realm was automatically set to itself 
I need this: 
If i create a new organisation new_org, its domain must be "new_org (organisation)"
if i create a branch new_org_branch, its domain must be "new_org_branch (organisation)"

I don't find the correct functions I have to use. Is it difficult?