#5 Please migrate to Guile 2.2

[Ahmed El-Mahmoudy]

Debian is migrating to Guile 2.2, hence if gwave doesn't migrate, it would be removed from upcoming release of Debian.

I tried building gwave against Guile 2.2, but the build failed, the build log is available at: https://launchpadlibrarian.net/405167257/buildlog_ubuntu-disco-amd64.gwave_20170109-2~2.gbp21df58_BUILDING.txt.gz