use forward decls in protobuf and create static sgproto lib
fix
fix
Add option to build static libshogun
Properly set -fPIC compiler flag if required
The libshogun object set should depend on the bundled libraries
Merge pull request #1757 from votjakovr/feature/gp_refactoring

Fix fail in FITC when number of latent features is not equal to number of training features