Routine update to 0.10.0, with some shiny new features.

The only dependent, lcsync, still builds just fine:

    $ ./pre-inst-env guix build --no-grafts --dependents librecast
    guix build: computing dependents of package librecast@0.10.0...
    /gnu/store/iygwf6rfbvm95544xyg9xr03fhbn02gq-librecast-0.10.0
    /gnu/store/nid8cf4ls28j1f523fz9np1xb2a121dv-lcsync-0.3.2

live well,
  vagrant