[Opensim-dev] Fix provider selection and possible security issue with plugins

[Ryan McDougall]

Details on mantis.

http://opensimulator.org/mantis/view.php?id=1852

Review and commit as usual would be greatly appreciated. Next step is
documenting the process of making a "new-style" plugin:
http://opensimulator.org/wiki/How_to_create_a_dynamic_plugin

Finally, I think the most important dynamic loading is done, outside of
RegionModules, which I haven't touched for now. The completed plugins
are:

IApplicationPlugin
IGridPlugin
IGridDataPlugin
ILogDataPlugin

The plugins I should also do because they are probably important:

IAssetProvider
IInventoryData
IUserData

The rest should be a simple transformation based on my instructions
(when they're finished). Anyone want to go for some low-hanging fruit by
finishing the process? 

IGenericConfig
IDataSnapshotProvider
IClientNetworkServer
IPhysicsPlugin
IMeshingPlugin
IRegionDataStore
IEstateDataStore
ITerrainEffect
ITarget
IDataNode

Lastly, is there a special meaning given to ifaces that end with Data or
Provider?

Cheers,