Unofficial Patch for OpenSim 0.6.9

Contents of corrections.

1) Fall to the hell
The phenomenon of avatar's falling to the hell is corrected at the boundary of SIM and
empty region.
However, there is a possibility of not operating normally in the Combine mode.
At 0 point this patch is well work, but at 256 point, it is not well work?

2) The message that the version of SIM is different only because OS is different is displayed.
It is modified that information of OS is not put in Version information.
If revision number of SVN cannot be acquired accurately, please write the revision number to bin/svn_revision file.