Bug#732436: Package should be multi-arched

[Scott Ritchie]

Package: libglfw2
Version: 2.7.2-1

While packaging a game, I discovered that this library is not
multi-arched.  The result was that another game using the library that
happened to be 32-bit could not be coinstalled at the same time,
leading to a weird random conflict between two unrelated games.  This
is now affecting real apps in the Ubuntu App Store.

Please multi-arch this library :)

Launchpad bug: https://bugs.launchpad.net/ubuntu/+source/glfw/+bug/941319