Ryzom

First, thanks for the patch :) I have some comments about it.

There is no conditional patcher and it'll be enabled for all builds so it won't work anymore with Ryzom Core shards (there is no patch system enabled by default). Another problem with this patch is that if data are updated under Linux and Mac OS X, binaries won't be patched (because only Windows client is updated via the patch) and so, client might crash (or bug) if it's not compatible with last data.

I suggest to either add a CMake flag to enable and disable patcher or make further tests in code to check if a patch server is working. Another fix could be to define what data versions are compatible with what versions of client but it's too much work for little benefices.

I'm thinking about a variable set to last version for gamedev.bnp or the data of the last patch in default_client.cfg. If the current version of gamedev.bnp or the date of last patch is lower than it, we can enable patch of data. So we'll able to update data only if binary and default config are patched by packaging system.