STLSoft 1.9.94: defective definition of swap() overloads for unixstl/winstl::memory_mapped_file corrected

As of version 1.9.94, the swap() free function overloads for unixstl::memory_mapped_file and winstl::memory_mapped_file are now declared inline, correcting a link-time error when linking multiple compilation units that use the component(s).