[mapguide-internals] MapGuide RFC 80 is updated.

[Leaf Li]

All,

Currently, MgParameter is similar to MgNullableProperty. The only difference between them is that MgParameter has one additional property "parameter direction". So according to Bruce's suggestion, I update MapGuide RFC 80 to construct an MgParameter by an MgNullableProperty instance and an MgParameterDirection value.

Can you review it?
http://trac.osgeo.org/mapguide/wiki/MapGuideRfc80

Thanks,
Leaf Li