NEW ISSUE: Co-occurrence constraints on sca-bpel:property attributeand sca-bpel:multiReference element

Title: Co-occurrence constraints on sca-bpel:property attribute and 
sca-bpel:multiReference element

Target: SCA BPEL C&I

Description:
A variable can either be a SCA property or an SCA reference (or nothing) 
in the introspected component type. But never both.

The spec does not say that a variable must not have both
sca-bpel:property='yes' and sca-bpel:multReference extension attribute.

Proposal:
Add the following to section 3:
In the introspected component type a variable cannot be both an SCA 
property and an SCA reference. [SBPELXXXX] A BPEL variable declaration 
MUST NOT have both the sca-bpel:property extension attribute with a 
value of "yes" and the sca-bpel:multiReference extension child element.

-Anish
--