#840 Debuan binary installer: libambulant* need adaption for MultiArch

[Kees Blom]

debian binary installer installs libambualant*.so for and architecture in /usr/lib
instead of /usr/lib/x86_64 as is now common. It works, though, potential problem
only when the same file system is used for different architecture (e.g.dual boot
a 32 bit and a 64 bit kernel). See sandbox/gstambulantsrc (was needed to adapt,
otherwise get-launch-1.0 would not find ambulantsrc).