SACM — ArgumentReasoning should also attach to AssertedChallange

This issue was raised by Sam Redwine on April 16th 2012 in a message to Luke and Nick

Argumentation metamodel:
ArgumentReasoning should also attach to AssertedChallange

In ArgumentReasoning class (previously 9.2.11), delete the first paragraph and replace with the following:
“ArgumentReasoning can be used to provide additional description or explanation of the asserted inference
or challenge that connect one or more Claims (premises) to another Claim (conclusion).
ArgumentReasoning elements are therefore related to AssertedInferences and AssertedChallenges. It is also
possible that ArgumentReasoning elements can refer to other structured Arguments as a means of
documenting the detail of the argument that establishes the asserted inferences. “
In the Associations subsection, add the following:
describedChallenge:AssertedChallenge[0..*]
Reference to the AssertedChallenge being described by the ArgumentReasoning.
Replace figure 9.1 with the following << figure on p 127 of ptc/2012-06-04>>