#21 Linux build fails. SimGear libraries not found.

[John D. Coleman]

Using git repository to build fgrun.
Build works up until this commit: Display aircraft thumbnail when the 3D model is not
Build fails until and including: Fix issue #957.....

The problem seems to be when calling the find_sg_library macro. The macro is called with the names of the arguments. It should be called with the contents of the arguments names.
IE:
You are passing SIMGEAR_CORE instead of libSimGear_core

Also,
I don't know about anyone else's system, but my system doesn't have any _RELEASE or _DEBUG suffixes on the the libsg* files.

Disclaimer: The above was written by a person that is NOT a cmake expert. Far from it. So I could be very wrong in what I think is wrong.