[mapguide-internals] Merging RFC 185 work into trunk

[Jackie Ng]

An update on this.

The volume of changes in this sandbox is so massive that I cannot svn
merge from this branch into trunk in one go, without my svn client erroring
out and me being uncertain about the state of my svn working copy
afterwards.

As a result, I will have to retry the merge, but now in a piecemeal fashion.

If you have MapGuide trunk currently checked out, avoid doing an svn update
on your working copy until I finished this (now multi-part) merge and have
given the all clear.

Thanks,

- Jackie