BaseContext :: executeLogin - Execute login function
The function is called, when starting up an application or opening a database. In order to check users permissions, the function has to be overloaded in an appropriate application or database context.
When the context handle does not refer to a valid context instance the function throws an exception.
Return value:  Success ( bool  )
The value is true when the function was executed successfully. Otherwise the value is set to false.
Implementation details
bool 
BaseContext  :: executeLogin ( odaba::Property &rProperty )
- rProperty
 - Property reference
A property handle refers to a (usually) opened property. Invalid properties may cause an exception. 

