Add Boost.Compute to the list of VexCL backends
Add Boost.Compute to the list of VexCL backends

ddemidov/amgcl,ddemidov/amgcl,dondieselkopf/amgcl,ddemidov/amgcl,dondieselkopf/amgcl,ddemidov/amgcl,dondieselkopf/amgcl