guile 2.0 and ghostscript 9.0

[Graham Percival]

What's the plan+status of these?

I'd like to have the first release candidate for 2.16 in 3-4
months.  If we think that we can sort out any problems with those
dependencies... or any other build dependencies, for that
matter... then let's start merging them.  If not, they can wait
until 2.17.

Procedure for any change in build dependencies:
- I will release 2.15.0, just so that we can verify all existing
  claim-closed issues.  I'm going to use GUB stable/2.14 for that.
- make sure that lilydev has all required (planned) build
  dependencies to compile git master.
- add these dependencies to GUB
- add these dependencies to configure

Cheers,
- Graham