Import Core from Fedora

From:
http://hans.math.upenn.edu/~edvardf/fedora-ocaml/SPECS/

Signed-off-by: David Scott <dave.scott@citrix.com>
Update to a more recent version

Signed-off-by: David Scott <dave.scott@citrix.com>
Fix the Core .specs

They now build on CentOS

Signed-off-by: David Scott <dave.scott@citrix.com>
Enable support for core/async through the stack

Signed-off-by: David Scott <dave.scott@citrix.com>
Update xcp-idl, xcp-rrdd, xenopsd

Signed-off-by: David Scott <dave.scott@citrix.com>
Core now builds on ubuntu

Mainly this involves:
  - running setup.ml -configure in the %build phase. It would generate
    the setup.data in the %prep phase and then lose it
  - fixing typos in the changelog
  - adding some missing builddepends

Signed-off-by: David Scott <dave.scott@citrix.com>
xcp-rrdd: changelog and release must match

Signed-off-by: David Scott <dave.scott@citrix.com>
textutils: move 'setup.ml -configure' to the %build (from %prep)

Signed-off-by: David Scott <dave.scott@citrix.com>
Move more 'setup.ml -configure' to the %build phase (from %prep)

Signed-off-by: David Scott <dave.scott@citrix.com>
Remove spurious 'Require'

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #550 from djs55/core-async

Add core/async and switch it on