addPrincipalMapping 
Add a principal mapping to use during user authentication. 
Location
/services/webservices/system/util/security/operations/
Request Elements 
The principal mapping to use: type, identifier, group.
Response Elements 
id: The ID value for the new principal mapping instance. 
Faults 
Illegal Input: If the input is empty or not a valid principal mapping. 
Security: If the user is not composite\admin.