Change build process to make libslicot optional on Mac OS X
XCode doesn't provide a Fortran compiler so Mac users will either have to find one precompiled or compile it on their own. Hence, libslicot should be optional in the build process.
XCode doesn't provide a Fortran compiler so Mac users will either have to find one precompiled or compile it on their own. Hence, libslicot should be optional in the build process.