Clarify use of IEEE754Compatible format parameter

In ODATA-342 we introduced the IEEE754Compatible for formatting Int64 and Decimal values as string. However, we didn't clarify or show examples of how this is used.

According to http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.7:

"Parameters MAY follow the type/subtype in the form of attribute/value pairs (as defined in section 3.6)."

Which seems to imply that Parameters MAY (or MAY NOT) follow the type/subtype, and if they do follow they would be in the form of attribute/value pairs.

We should therefore clarify that the IEEE754Compatible format parameter with a value of TRUE means Int64 and Decimal values are serialized as string, and a value of FALSE (or omitting the parameter) means that Int64 and Decimal are serialized as numbers.