In this directory you can place addon modules for OpenSim

Each module should be in it's own tree and the root of the tree
should contain a file named "prebuild.xml", which will be included in the
main prebuild file.

The prebuild.xml should only contain <Project> and associated child tags.  
The <?xml>, <Prebuild>, <Solution> and <Configuration> tags should not be 
included since the add-on modules prebuild.xml will be inserted directly into the main prebuild.xml